rebel rp has a fundamental problem in terms of risk
if the only place rebels can go to is at constant pk risk from sweeps, there will be no rebels it's impossible to survive. if there is no pk risk at all, everyone will be a rebel no one cares about the risk. hidden bases used to be the way you picked some rebels and said 'we're gonna give them a way to survive'. but this feels unfair, because not everyone has access to them - and as soon as you increase the access to them, cops will raid them and they'll be immediately destroyed. you might think 'well thats okay, because then you just have lots of rebels'. but you get the second problem which is that you massively split the playerbase, when 70% of the server are swinging guns around underground with no risk, there's no one in the city for cops or new players to interact with and the server begins to die out. so you need to force rebels to the surface to interact with players.
the solution to this fundamental problem has always been subtle rebel rp, but most server operators are not willing to do what it takes to facilitate this. to create subtle rebel rp you either need to allow for hidden containers (which there will be a stupid amount of), hidden bases (which require management and some feel is unfair) or publicly accessible containers.
the best all around solution so far has been publicly accessible containers, but for some reason the staff only put them in places that aren't useful - the middle of the city, or the middle of the underground. and never where they're actually helpful, the slums - where they can be a middle ground between rebel and city life.
everyone knows large hidden bases are bad, people should not be roleplaying in areas cut off from the rest of the server population. smaller hidden bases for the purposes of storage are convenient but require excessive management of the knowledge and information regarding these bases.
a nice alternative that doesn't quite do the same thing as hidden bases but does increase rebel safety are one way doors. by creating one way doors, especially hidden ones - rebels are able to outmaneuver cops and utilize alternate routes to escape sweeps.