They should have a cheat code, "Gang War", different from SA in that you can make people into gang members by giving them different colored bandanas. This way, we could turn bring every citizen on the street into the gang war.
You could even give them certain weapons by gang, person, or just random
But bring back the San-An "Follow Me!"/"Disperse" actions, and hopefully the AI will be better and try to get away from burning cars or even be able to follow you in a timely matter, though in GTA4, for instance, when you first meet Jacob and he follows you to your car you have to walk SO SLOW!!! or else he gets caught on the corner of a building and forgets what he's doing... I hope thats fixed