Great topic!
For me, playing on HC and a lot of the time I solo, this is how I rate them:
Freeze/Stun can cause death. So they are #1 enemy in my book.
Slugslider can be annoying because he can fill a screen quicker than I can kill them = force to remake. Spawners (Slugslider, Gigapede, the Bee one, Camoslauge, Frisp, whatever else can spawn) take #2.
Physical Defense (Foglime, Goochi) take #3 just because I don't cast and they slow my exp/hr down when they do their dirty deeds.
The rest I can deal with but my top 3 are annoyances, ranging from minor (#3) to pain in the ass (#1 and 2)
e: Almost forgot... the damn multi-healers... when they spawn one on an EP wave, this can be a chore. Just when you think you have an EP dead, his buddy multiheals him and he's at half+ HP again. Honorable mention.
Also, please dont take my post as a "crai" post. I love the challenge, and am very glad it's in the current state of the game. Just because something is annoying doesn't mean it does not work well. I'm glad the monsters can do this, it adds to the challenge of the game and makes my climbs that much more butt-puckering.
This post was edited by jlhromeo on Sep 22 2014 05:34pm