if you are currently using vcas as attenuators I see nothing wrong with adding a trim module to free up vcas - in fact probably what I would do - unless there is anything else you feel is missing - or just leave it for now - you don't have to have every case full to the brim!!
"some of the best base-level info to remember can be found in Jim's sigfile" @Lugia
Utility modules are the dull polish that makes the shiny modules actually shine!!!
sound sources < sound modifiers < modulation sources < utilities