A Good idea would to add in basket ball courts where you can play chilled out games like in nba 2k its called mypark and would seem a good idea in a game like
this, also other ideas could be boxing gyms or gyms in general.
A Good way for this game to be free would be the idea of organised crime like drug dealing, smuggling and good transport would be a very effective way to get money, make a name for your self and bring heat to the game. This would bring many other aspects to the game and would make full effectives of the games police officers and also meaning of power trying to control the map.