It has probably been considered, but if not, it may be useful to investigate moving to GIMP for the bitmaps and texturing. That would eliminate some licensing fees. Of course there would be an initial "learning curve," but for the basic tasks this would be small.
The switch would also make repainting more accessible to the users. Every time I do a repaint, my first steps are to load the photoshop files into GIMP, then adjust the layering. I continue on from there, working only with that program. It has always been adequate for the purpose.