How are you painting these guys up? I only have MS Paint it take quite long time to fill in the blanks.
I'm using GIMP, which is a freeware graphics program. My process requires some degree of layering, which means that preparing the 'template' for each 'Mech is the hardest part of it.
I've been trying GIMP and been having major issues trying do it. I had to have a friend who knew GIMPs help me until the table/tools got hidden and I could figure out how to get them back. It's not a novice thing for certain.