Good post mate, lot’s of good thoughts mostly agree with you, but would like to discuss some points with some different opinions 
If it is a powerful skill with a cooldown, that makes frenzy/WW or other builds more powerful and versitile fighters (obviously sacrificing pts in utility skills like find item/BO etc) than S-tier. If you just stand there jumping up and down until everything is dead, than F-tier (I want to see more complex, rewarding, and strategic combat mechanics)
Armageddon is already an A-tier skill in my books. Trust me, if you know how to play fire druid already, these will make fire druid much more powerful… Casual fire druids struggle with survivability and so are afraid to telestomp big packs… But if you telestomp big packs, armageddon wrecks them…
I’m really disappointed with this change. If copying what PD2 and PoD did, or making the summon druid play like “a summon necro with furries” is their solution, then why did we pay Blizzard $40 USD or $70 AUD to copy paste ideas from other designers? Would rather they make D2R mod-friendly, then people who prefer “Zoo Druid” can play that style in one of those mods. In D2R, this change throws out PvP balance, makes poison creeper/spirit of barbs irrelevant, and reduces build diversity or creativity (no point getting creative if birds/wolves/bears all synergise each other and meta-tactic is to cast them all at once). F-tier change in my books…
Yes, strongly agree… A3 merc is so close to greatness (for example, I love the static merc on many builds). His biggest problem in my experience is survivability as he cannot leech life from his spells… Devs need to improve this badly, otherwise he is impossible to use without teleport or summons to tank for him. Ironically, summon druid changes might help fix this problem.
Annis need to hold their value and be worth something… They are an incredibly powerful item, +1 all skills to any class, +attributes, + resistances, it needs to be hard to obtain… Selling SoJ’s is synonymous with this and part of Diablo’s rich history and story over the years… There will be plenty of D-clone spawn events, just join one of the Diablo Clone Hunting Discord servers, and you will get announcements from people who hunt D Clone, it is actually really exciting and fun, and rewarding to finally catch D Clone . B-tier or A-tier change