I think it would be a fun idea to make gang sheds raidable. For example you would need to boltcut the door and plant a blasting charge on the smaller door. Once you start bolt cutting it would send the members of the gang a message that their Shed is being raided. Once the bomb blows you would have access to their crates and T inventory. However you couldn't just raid a gangshed at anytime... There would need to be 8-5 members online to raid their gangshed.
Not sure if this would work, but I think it would be pretty fun and would be another gang v gang activity other than cartels.