Hello Everybody,
I wanted to share several of my ideas coming from experience about co-op commanders and mutators and how to make them more exciting, balanced and logical. I also included several ideas of my friends as well as others on the forum which I also found good ideas.
Note that I wrote them as facts, as they would apear in the patch notes. They are just ideas which I’d love to see live.
Oppinions are welcome! 
General:
-Commanders’ level talents use corrected grammar and explain their changes with exact numbers.
-Vipers cannot abduct immobile units.
-Amon’s Motherships gain 100% increased life and shields.
-Amon’s Ghosts can no longer call down nukes on high ground without vision.
-All kinds of infested structures gains both the Biological and the Mechanical tag. Bio dome changes from Light to Armored.
-Gift exchange mutator available in Custom mutations.
Raynor:
-Spider mines return to their original place if not triggered for 5 seconds.
Kerrigan:
-Immobilization wave slows down Massive units instead of freezing them. Heroic and Massive units take only half the damage from it.
-While using leaping strike and psionic shift Kerrigan takes 20% less damage.
-Chain reaction prioritizes air units.
-Level 15 talent ‘Queen of Blades’ provides the ‘Improved overlords’ upgrade (from Heart of the Swarm) which makes overlords to morph instantly and provide 50% more control (supply).
Artanis:
-Archons’ starting energy is equal to the two templars’ actual energy altogether. This means that their starting energy can be 400. This extra energy does not get lost over time, but if it gets below 200 it cannot go up above it again.
-Archons deal double splash damage and their psionic storm deals double damage and restores double shields at twice speed to friendly units while their energy is above 200.
-Archons’ starting life and shields are equal in percent to the merging templars’ same stats’ average.
-Archons can pass through friendly units.
-Tempests have no separated attacks for ground and air. The ground attack’s stats apply against air units too.
-Desintegration deals 500 damage under 10sec, down from 20sec.
-Desintegration deals splash damage in a 1-range area around the targeted unit. Total splash damage is 100 under 10sec.
Swann:
-When using vespene harvester for the first time, both players hear the other commander’s thanking.
-Level 1 talent’s description re-written. It states 20% faster production than “base rate” instead of “other commanders”.
-SCVs benefit from the ‘Regenerative biosteel’ upgrade.
-Cyclones gain increased damage, dealing 24 vs massive which increases by +4 with each upgrade. This does not effect the lock-on ability.
-Cyclones gain +2 attack range and lock-on range.
-Cyclones’ lock-on ability decreases enemy units’ attack speed and movement speed by 15% in a 2-range area around the targeted unit.
-Thors have their ground attack range apply for air attack as well. Parallel with this they prioritize to use the bigger damage-dealing attack against their targets.
-Level 13 talent automatically provides Wraiths the ‘Tomahawk Power Cells’ upgrade (from Wings of Liberty) which gives them +100 starting energy.
-Wraiths reduce all incoming damage while cloaked by 30% replacing the 20% evading after research.
-Wraiths automatically cloak themselves at the first time their health goes below 50%. They do not lose this ability if they are already cloaked.
Zagara:
-Kerrigan’s Level 4 talent ‘Spawning pool upgrade cache’ 's description copeied to Zagara’s Level 6 talent, because they both provide the same.
-Fixed the population indicator to no longer mess when it comes to 1/2 and 1/3 supply in case of Drones, Zerglins and Scourges. It writes the higher number instead of following the rounding rule.
Vorazun:
-Dark archons can pass through friendly units.
-Corsairs do not place multiple distruption webs at places that are already covered by this ability.
-Time Stop reveals objectives even if it does not effect them.
Karax:
-The commander is included in Zeratul’s after-match ‘Shields restored’ stats similarly to how Stetmann is included in Zagara’s ‘Damage done by Banelings and Scourge’ one.
-Nexus chrono activates automatically for all protoss commanders when paired with Karax and for him as well.
-Level 5 talent ‘Chrono overload’ effects gas harvesting structures, adding +5 gas every second per structure.
-Each ‘Solar efficiency level’ research costs -50 minerals and gas.
-Energizers gain increased damage, dealing 12 vs biological which increases by +2 with each upgrade.
-Reclamation’s cooldown changed to 90sec, down from 120sec.
-Reclaimed units add to the supply count.
-Energizers can attack and cast chrono beam simultaneously.
-Shadow cannon’s cooldown changed to 30sec, down from 45sec.
-Mirages’ attack reworked, dealing bonus dmg vs armored instead of light.
-‘Chrono Wave Energy Generation’ mastery replaced with ‘Spear of Adun Cooldown Reduction’ (effecting: Solar lance, Chrono wave, Purifier beam and Unity barrier). Each point adds +1sec. Initial cooldowns are not changed.
-‘Repair Beam Healing Rate’ mastery renamed to ‘Reconstruction Beam Healing Rate’ and reworked. Each point adds 2,5%.
Abathur:
-Limited to 100 supply.
-Level 13 talent ‘Locust injection’ replaced with ‘Automated extractors’.
-Toxic nests on autocast explode when the 1st enemy unit gets farther from the middle point, instead of exploding when a unit touches their edge.
-Brutalisk and Leviathan morphs’ autocast removed.
-Only those units have a yellow flash which collected 100 biomass. Under this quantity they only grow in size.
-Brutalisk morph costs 300 minerals, 200 gas and 4 supply.
-Leviathan morph costs 350 minerals, 150 gas and 6 supply.
-Symbiote targets the host ultimate’s primary target (if it can reach it).
-Level 15 talent ‘Biotic leech’ replaced with ‘Evolution Professor’ which allows Brutalisks and Leviathans to collect additional 25+50 biomass. For the first 25 biomass they gain +0,5% per point increased attack speed and life regeneration and their symbiotes also receive this attack speed. If the 25 biomass is collected the symbiote gains +1 attack range. The further 50 biomass do not change anything for them. They carry and give those to the 1st player unit that gets within 1 range.
-‘Double Biomass Chance’ mastery replaced with ‘Maximum supply’ which adds +1 per point.
Alarak:
-Alarak can be selected and moved at 4:00 into the game.
-Death Fleet’s initial cooldown set to 360sec.
Nova:
-Level 1 talent’s description enforced, units are indeed resistant to stun effects (special infested, void slivers, mutators, etc).
Stukov:
-Level 1 talent allows the Micro filtering upgrade which makes SCVs gather vespene gas 25% faster (bringing 5 each trip).
-Volatile infested and Broodlings follow the Psi emitter’s signal.
-Level 3 talent adds 20% chance for Infested civilians to spawn as Volatile infested.
-‘Volatile Infested Spawn Chance’ mastery replaced with ‘Factory and Starport Unit Life Regeneration’ which adds +3,5% regeneration speed per point.
-Infest structure gains additional 1 charge with each Infestation level upgrade.
-‘Infest Structure Cooldown’ mastery reworked. It modifies -2,5% per point.
-Infested troopers live for 15 seconds outside of the bunker.
-Infested missile turrets benefit from bunker and marine upgrades (double as fast life regeneration, +3 armor, +1 attack range and plagued munitions).
-Level 13 talent provides Brood queens with +100 maximum energy too.
Fenix:
-Level 1 talent’s description enforced, suits do not regenerate energy within Stetmann’s J.U.I.C.E. configuration.
-Conservators have higher selection priority than distruptors.
-Distruptors cost 3 supply.
-Purification nova’s cooldown decreased by 5 seconds.
Dehaka:
-Primal hives, wardens and wurms do not cost supply.
-Primal hives and wardens are not included in All army selection.
-Greater primal wurm’s tech requirement is Primal warden.
-Greater primal wurm’s basic charges are 2, but it gets an additional maximum charge with each Pack leader building.
-The first Greater primal wurm does not start on cooldown.
-Greater primal wurms’ deep tunnel has a 15-second cooldown.
-Basic gene mutation chance increased by 50%.
Han & Horner:
-Maximum 3 Magmines activate on the same target at once.
-Hangar bay upgrade costs -50% gas.
-Hangar bay’s tech requirement is Engineering bay.
-Level 11 talent ‘Endurance training’ also allows Fighter drones to repair the host Galleon while out of combat. The repair speed depends on the number of fighters. Each unit repairs 3 life per second.
Tychus:
-Medic AI issued on Nikara.
-The Odin has its ground attack range apply for air attack as well. Parallel with this it prioritizes to use the bigger damage-dealing attack against its targets.
-The Odin can be targeted by anti-air attacks.
-Auto turrets benefit from attack and armor upgrades.
-Cannonball gains the Massive tag.
-Vega’s dominated units add to the supply count.
-Vega’s damage is increased by +50%.
-Nux deals double damage vs Massive units. This does not effect Ultrasonic pulse.
Zeratul:
-When paired with Arcturus the Enlistment center is no longer covered with a blue shade.
-Level 3 talent’s description corrected about the Ambushers’ void apparition’s damage (50% instead of 200% as it was previously changed).
-Ambushers teleport away from the place the threatening damage came from instead of teleporting backwards.
-Shield guards do not activate reflective shield on autocast if they are within an activated field.
-Abrogators’ purification nova does not add to the ‘Units produced’ stats at the end of the mission.
-Avatar of Form’s Charged crystals are included in the All army selection.
-Shade projections have -30% cooldown if the previous projection was not destroyed.
-Serdath legion can pass through friendly units.
Stetmann:
-Level 15 talent ‘Mechnum Opus’ provides the player’s combat structures with 50 egonergy and makes them benefit from stetzone configurations at a 25% efficiency. Spine crawlers benefit from ‘Hardened egonergy shield’ Zergling upgrade, Spore crawlers benefit from ‘Tyr-class targeting system’ Hydralisk upgrade, while both benefit from ‘Synthetic adrenal pumps’ Zergling upgrade.
Arcturus:
-Medic AI issued on Intercessors.
-Intercessors do not pick up units they are rallied to upon creation.
-Witnesses in patriot mode have lower selection priority than troopers.
Mutators:
-Safe zone corrected on Oblivion express at the left base.
-Mutators do not target nor damage objectives.
-Aggressive deployment does not drop in safe zone.
-The first Void rift spawns at 4 minutes into the game.
-Heroes from the Storm on Dead of Night spawns heroes at the start of each night and with each attack wave instead of 6-10 heroes during the 2nd night and so on. Heroes no longer spawn with waves that come from Nydus worms.
-Heroes from the Storm heroes are not immune to Dehaka’s devour ability.
-Heroes from the Storm heroes have -50% life.
-When Transmutation is active special infested, Dehaka hero and each race’s hero ships (Loki, Leviathan, Mothership) do not transform into anything else.
-When Polarity is active, uncontrollable abilities do not target enemies that they cannot damage.
-Avengered units receive half the improvement towards their attack speed and life regeneration.
-Power overwhelming’s Point defense drones no longer block players’ top bar abilities (like Concentrated beam) and unit abilities (like Yamato).
-Power overwhelming units can be targeted by Feedback.
-Power overwhelming units cannot use abilities if they are stunned.
-Power overwhelming abilities respect safe zones.
-Massive units take 50% weaker and shorter effects from Fear, Fatal attraction, Blizzard, Twister, Time warp and Concussive attacks.
-Temporal field causes Massive units the same slowing effects like it does to Heroics, instead of freezing them completely.
-Heroic units take 50% shorter effect from Moment of Silence and Fear.
-Fatal attraction and Moment of Silence have -40% range.
-Fatal attraction does not pull immobile units (including lurker and mine types, sieged tanks and detector units that are switched to immobile mode)
-Concussive attack’s effects last for 20 seconds.
Hope to hear from more and more people.
With best regards,
Mazso