Awesome work, I see those display cabinets and dioramas in my wildest dreams! Spectacular.
Probably not news to you, but I use Johnstone's Ultra Primer on surfaces like plastics, quick abrade with soft paper to provide a key then Ultra primer... makes a really sound surface for any decorative paint. It should prevent the wrinkling paint issues. (btw I'm a decorator but with I had such fine skills as yours!)
Always love your updates, good arrows Sir.