You may be right, but also take this into consideration. 90% of the people that play this game drive like mad men. Nobody would use the streets. Some **bleep**s are bound to stay in one spot and spawn kill anyone who regenerates. There would be no point. No civilians running around or anything. Maybe if they had it to where there were only maybe 4-6 per server, and you could get together with some friends and take civilians out, or help each other out with online-only missions. But the whole mass-gang-war idea is going to be a flop.
I think, GTA 4 should be online, i agree 100% that would be so sick, everyone would be killing people. But I dont agree it should be just real people on the streets. i think they should still have regular civilans so you still have fun running them over/killing them/decapitating them or what not....,