Sometimes you love everything about a game, except for that ONE thing. That one thing annoys you every time you play and you wish so badly that you could just go back and get that one thing changed/removed from the game...
Here's mine: The original Starfox got me back into gaming after I missed the entire NES era. So naturally, I was greatly anticipating Starfox 64 when it was announced. I couldn't wait to see what they could to with the improved hardware. Starfox 64 was one of THE reasons I went with the N64 instead of the Playstation.
So, at the time Nintendo was trying to prove that carts could be just as good as CD's in terms of multimedia. Specifically, they were touting that Starfox 64 would have as much spoken dialogue as a typical CD-based game, and boy did it. To this day, I find the voices to be almost universally grating with Slippy being especially annoying. The game sounds like a Nicktoons show and I wish I could go back and tell them to lose the voices, they're so unnecessary to the game and didn't prove a thing in the cd vs. cart debate.