SPOILERS:
I know it's already been mentioned, but I wasn't very fond of the ending of Mass Effect 3 - I didn't like how you simply picked an ending similar to that of Deus Ex: Human Revolution (wasn't fond of that ending either), either a blue, red or secret green and they're all similar. I didn't like how all the mass relays were just destroyed and left everyone stranded just outside, or on earth. I do honestly prefer Bioware's extending of the ending with slight changes, but I feel they shouldn't have needed to resort to that to begin with, you know?
The ending of Metal Gear Solid 2: Sons of Liberty didn't sit well with me either - I thought it was very confusing and it really just felt preachy. I thought the plot of the whole thing being one giant potential VR mission to create an army of Solid Snakes was kinda silly too.
Splinter Cell: Conviction's ending wasn't great either - How you're given a choice to kill the villain, or to spare him only to have Grim kill him instead... and if she does, Sam is all "You didn't have to do that" or whatever. The game doesn't give you moral choices or anything. You have to kill most of your enemies anyway and Sam tortures people, brutally. I think they should have made the final cut scene non-interactive. They should have made it that Sam either kills the guy himself, or Anna does it.
Resident Evil 6 had pretty bad endings too... I liked how Chris' campaign ended, but then - it became stupid when he's in the pub, wearing a TURTLE NECK AND CHAIN. What Chris, did you "juuuust have seeeex?!"
