A while back I found this add-on python script for Blender which I save to my “downloaded models” folder. It’s got a series of miscellaneous scripts, one of which being UV unwrapping tools…it can create UV unwrapping perfect for Blender’s painting system, designed for chaotic meshes.
It works fantastic for models I make in Sculptris and then decimate in Blender, but not so much for models made entirely in Blender, even if I decimate it. I used to use Smart UV Project, but it creates seams with pretty much anything. Granted, the models that need painting the most (animal/human models) are made in Sculptris; but once in a while this script gives me major problems and drives me nuts.
There’s always an easier way to do things though, if you can adapt. Turns out in this case, using the default unwrap tool was it.
All to make this sprite:
(though granted there will be more color varieties)
P.S.: if you’re a blender user and want to see those addons, go here: https://github.com/vilemduha/blender-addons-vilem-duha/tree/master/addons