I do like how you say that "the cops would most likely just shoot you and the hostage on sight with no consequences". Have you been in a position so far that makes you able to back this opinion up? Also this city is RP for being allowed guns, having gun stores on multiple streets and a license to own a gun, so what cop in their right mind would shoot you for holding a gun. A cop may as you to holster it and give you a warning but they would just handcuff you or taser you for not listening (unless you aim your gun, then you are shoot-to-kill). So long as the civs can role-play a gun scenario better, the cops are going to be less on-edge that it may just end up in a stupid shoot-out because that's what a lot of people see GTA as.