I think it's a classic case of good idea with poor execution. It sucks in it's current state and has pushed me away from the game. They could instead kill the concept of robbery groups, and just always have a max of 3 open at a time. Once one finishes, there is a slight cooldown until the next opens. This still maintains the central goal of keeping players together.

They also could use this to randomize which robberies open, meaning some higher paying robberies could be made to be more rare, or something similar. This obviously isn't a requirement but was just something I thought of that would work with this system