Welp, Campaign is beat.
I'll separate my thoughts into two catagories: non-spoiler, and spoiler.
Firstly, from a mechanical perspective, I felt the campaign was weaker than WoL's. The missions are overall less interesting, the characters are far weaker (though really, how do you make zerg interesting since it's a fucking hivemind) and the "Hero level up" system, while cool, is mostly useless if you actually know how to macro at all. It does make you feel like you're this incredible psionic zerg queen, though.
The "in between" parts are far less interesting. I found myself eagerly looking forward to exploring the Hyperion and talking to everyone after each mission in WoL, in HotS the characters are boring for the most part. I found myself missing Tychus and Tosh and Matt and the News station girl/guy.
Alright, spoilers follow. They assume you've beaten the game.
[spoiler]Kerrigan's new form was cool, I could dig the ghost suit with zerglocks, but then she gets a new transformation...right back into original fucking Queen of Blades. Now, I like the Queen of Blades look, but shit.
Wow, Duran/Narud went down like a fucking chump. I really, really hope that wasn't it for him. I mean, come the fuck on.
Wow, Mengsk went down like a fucking chump. I did like the part where he swiveled around with a cigar in his mouth all JUST ACCORDING TO KEIKAKU though. HEY MENGSK MAYBE USE THE ARTIFACT TO SAVE YOUR FUCKING PLANET OR SOMETHING INSTEAD OF SAVING IT AS YOUR FINAL ACE IN THE HOLE BUT THEN LOSING ANYWAY BECAUSE YOU GOT CAUGHT MONOLOGUING
Thanks Jimmy. For everything.
Note: Kerrigan died on the way back to her home planet
OH NO AMON IS BACK MY OLD GOD BACK HEY NOWWWWWW, HEY NOWWWWW, MY OLD GOD BACK
guess we better head to hyjal to have a three way team up to stop him from destroying the tree of life or whatever[/spoiler]
all in all, I rate this game 7 banelings being kited by 10 marines cause you're off creep and you haven't finished speed yet