The fact that Sonic Riders 2: Zero Gravity wasn't released on PS3. Although not an unpopular opinion I really enjoyed the game and was it was disappointing to have it not on it or 360. I haven't played much Sonic games in the recent years (Sonic and SEGA All Stars Racing being the sole exception for new games, and revisiting old games like Sonic The Hedgehog, Sonic The Hedgehog 2 and Sonic Adventures.) So I can't really say much about them.
Although if I recall correctly, one thing that did make me hate Sonic Adventure 2 Battle was having to play as Tails (and Eggman I believe?) in a machine. It has been to long to remember if you could play as Eggman in that game (pretty sure you could.) I hate machines and generally avoid games (other than racing games, and these are mainly like Mario Kart) that have machines in them.