I suggest, that the ticket lock operation should be an async operation in some cases.
If I want to do a bluk action on tickets, OTRS locks all selected tickets. If I have around 100 selected tickets I have to wait quite some time until I can specify my wanted actions.
Of cause I shouldn't be able to submit my changes until all tickets are locked.
Since ticket locking isn't invulnerable to race conditions between agents I don't see any risk associated with async locking at bulk actions.