DayTripper seems dead in the water to a large extent, and Unique always seemed a bit superfluous. The problem, IMHO, is when you don't really have a critical mass of vehicles such as Tin Coaster. Unless you have a dedicated allocation, such as Mousehole or Falmouth Coaster, then it becomes a challenge to manage.
For the Coasters in Cornwall, have 32179 in Falmouth, and number in Lands End (LEC) and Atlantic (AC) variants, and then perhaps a few in some sort of neutral scheme? Not dealer white but something promotional that can be used across the various routes.