I would put it in this order
WoL
NCO
Can’t rank HotS and LotV in order below it. They both have hits and misses for different reasons so are hard for me to compare.
LotV was fun for the Spear of Adun perks and army composition system allowing you to tailor your army to fit the mission. However, only a few missions were memorable. My second time around I counted 11 out of 19 missions that were specifically to capture/destroy five objects scattered around the map and the maps were usually bland arena style maps that felt like they were mirroring how they were designing coop too much.
“Armory” system was a missed opportunity. After the first few missions too many categories make you choose either/or with completely different units, which completely shuts down army comp dreams I had for it. I would have loved to play a big diverse fleet tactic in some of the missions but couldn’t since most air units fell under this category. What would have made more sense is to have some sort of slot system allowing you to select and deselect units for your army, only disallowing you from choosing more than one variant of the same unit. Perhaps one SoA perk could have been to unlock additional slots for people who want diverse comps, or to you know have carriers and mothership together.
SoA abilities did kind of become a crutch that reduced the challenge. The campaign format felt a lot like Mass Effect 2: find and recruit allies and gain their loyalty to join you in the suicide mission finale, broken up by a mid-game confrontation and escape from the main enemy. It is also worth mentioning that the prologue and epilogue missions tied to it are the ones I found the least replayable/enjoyable.
HotS had too many hero missions of mass right clicking and ability spam, adding in complex boss fights with telegraphed attacks. Those missions felt more like Diablo 3 than Starcraft so points off for those. Too little zerg air was featured and too many evolution missions which were, at the time of release, a loading screen as long as the actual mission on my computer to accomplish what the video demo could have. They should have spent more time putting in a way to unlock corrupters, scourges, and other morphed air forms like devourer and guardian. I found myself relying too heavily on Kerrigan mind blast for air units. Her abilities did tend to trivialize the difficulty as the game went on.
Nova was a nice breath of fresh air for a lot of it, giving a return to bigger maps with stuff to explore, extra objectives and a variety of mission types. Some I even got to enjoy up to an hour due to no hard timer. I found the army customization system very appropriate for the theme of it. Only disappointment was the final mission’s “boss fight” emphasis.
WoL was my favorite because it felt closest to a BW style campaign. The objectives and maps varied a lot and required you to make use of a number of approach strategies instead of just “death ball to 5 big rocks” repetitions. Some missions make very specific use of Terran-specific abilities. It is literally the only campaign that ever requires you to use transports at some points. The main “bonus ability” is simply the merc compound to buy instant reinforcements which helps keep mission challenges intact later game. I did find some missions like The Dig to be a little too monotonous and overly simplified by single unit spams but I found diverse comps worked well even on brutal. I wish the archives after the campaign was complete would allow you to reallocate research and credits to replay missions differently, and allow you to play the alternate version of All In that you didn’t select during playthrough. It isn’t a deal breaker as I always enjoyed replaying it.
I appreciated armory/research decisions being permanent as you make some missions easier and some harder for yourself in that approach rather than reallocate throughout the game to make each mission the easiest possible. Love the Terran soundtrack and the fact that you get the whole arsenal unlocked.
I didn’t dig too much into story because honestly, I enjoyed the way the BW story was done, not due to a headfirst dive into the weeds to analyze specific plot details for threads on end but because at a high level they are like two different stories. SCBW is like a TV series, heavily emphasized on plot development and twists, bittersweet victories and long term consequences of some of the missions completed. It’s objective is often to keep the plot going. It used first person storytelling and used map design to create difficulty in macro, micro and approach.
SC2 was like a movie series. It is structured more as a mass market fantasy trilogy with each campaign having a few main events and is very cinematic. The story emphasizes perfect victories as canon and seeks to bring total closure to the story. It focuses more on gameplay that is more divorced from traditional melee play with varied starting conditions and emphasizes unique units and abilities with enemy strength and number varied for difficulty. It also more heavily emphasizes time limits for missions. They are just two very different games so people’s preference will gravitate toward one or the other based on what they are looking for. That is probably what drives my preference.