I just played through CK1 for the first time ever and beginning CK2 after vaguely reading through some of the forums and here have been my thoughts so far:
COLLEGE KINGS 1:
Overall, the story was pretty good and I would say better than the majority of AVNs I've played - hell, I'd through it in my personal top 5. However there were some consistency issues that really bothered me.
Some annoyances I found is that in a game where the story is centered around becoming the ultimate fighting champ, most of the fights are just timed reactions of "dodge" "run" "punch" instead of using the actual minigame they developed which I felt was strange. I get it, not everyone wants to play minigames in an AVN, but they're great for changing the pace of just clicking through dialogue and making it more interactive. The Murder Mystery for example, was a great change of pace and fun to strategize and play through.
Speaking of Murder Mystery, holy fuck the free roams are so annoying to navigate. I found myself looping through areas on accident numerous times even on multiple playthroughs for new routes. You're basically a mouse running through a maze just guessing where you're supposed to go based off of scent.
Europe trip: Overall, a lot of fun but there isn't really a big underlying story moving but rather a DLC main quest filled with a bunch of side stories. Yeah, you can argue the Chris/Nora relationship or the Chicks drama as the main moving pieces, but it doesn't feel like a big main story objective that's moving along but rather mentions of it while going on your 20th side quest.
COLLEGE KINGS 2:
I've barely started it but my biggest annoyance right now is how you have to wait for a 2 second animation of a mouth opening/closing before getting the dialogue. I tend to read fast and it feels like everything is getting dragged out just waiting on those animations alone. The animations themselves aren't bad and add further immersion, but waiting for them over and over again before the dialogue is driving me nuts and making it hard for me to want to continue.
