I think the gang stuff needs something more structured. At the moment there is nothing but gang listings/logos in profiles... would'nt it be better to have actual gang listings/pages in the game somewhere. Where you can actually see who is in which gang, how many members, gang rankings etc. Maybe an element on the page where you actually have to apply to a gang to be accepted. 

To take the idea further maybe gang battles at the click of a button, with all gang members drawn against an opposition gang member.

Gang bank account, which could be used to increase ammount of members possibly. It could be raided by having gang wars.

Gang store, to house all gang weapons items etc.

Better training perks or something with bigger/more powerfull gangs.

I'm sure there are lots of ideas could be thrown into this. Easy for me to say though, as I don't do have to do the programming.