I might be a little late but the things other games did better were:
crackdown: great platforming and far better aiming (and I only played through the PC version of GTA: SA). even the vehicle controls were better. don't forget it had great co-op.
Saints Row: similar type of game to GTA but SHOCK, you could shoot well! Did most of what GTA did but more polished. and with decent mulitplayer.
Assassin's Creed: ridiculously bitch slaps GTA in amount of people on screen, AI(!), interactivity with the environment, and apparently also the movement controls!
the only thing GTA has actually going for it are the size of the cities (being realistic/spread out) and capturing the atmosphere of what ever theme they're going for. the gameplay sucks though. in the PC version, it's sort of tolerable as a game you can pick at whenever you want because the controls for cars and shooting is vastly improved. It's a shit ass game to play on consoles though. don't kid yourself. I do, however, like the humor and the stories. it's maybe sitcom quality and I usually don't mind sitting throught the movies.