After clocking a lot of time in this game during the beta, much hasn't changed in the ways Cops play.
I was thinking about maybe moving the Cop base 2 (since no one really uses it) or making a new Cop Base at the prison. This would allow Cops get to the prison easier for my next suggestion.
Make Guard Stations near the prison that cops can stand guard at. By Giving a few cops of watching prisoners, we could make the prison more susceptible to prison breaks from the outside. Pretty much the only way to get out of prison is to get airlifted. Prison breaks would add an element of fun to the game and would allow for cops/criminals other than just random shootings.
In order to make it more fun, you could have instead of autojail to the prison. You are autojailed into the Cop Base in a holding cell. However, the time you could spend is limited say 5 mins max. If you want to spend more time you must transport the prisoner to the main prison. The autojail for killing at copbase could stay, yet just change it to autojail to the holding cell. (That way there is no assault on the copbase).
Another way to facilitate this too is with the local jail that was mentioned, maybe there could be a convoy misson like there already is, but instead of weapons its a High Value Prisoner that you have to transport from the cop base to prison, this would give cops/criminals something to do when no one is really comitting crimes. You could get payment for breaking out the prisoner on the way to the prison and if it successful delievery by cops it would en. Maybe have it work 2 ways so cops can get an extra bonus for doing the tranpsort andvis get bonues for breaking him out