Non-composite CGA modes in DOSBox seem to be duplicated. There are "Tandy-style" CGA modes (vga.mode==M_TANDY2 and vga.mode==M_TANDY4) and "VGA-style" CGA modes (vga.mode==M_CGA2 and vga.mode==M_CGA4) depending on the selected machine. Is there is a good reason why this needs to continue to be true, or did it just end up that way for historical reasons?

I ask because while doing the composite patch I noticed some bugs in the M_CGA2 and M_CGA4 modes (they don't have aspect_ratio=1.2 and in VGA_CheckScanLength they always have vga.draw.address_add=80). There are probably other similar bugs as well. We could fix such bugs as they are discovered, but it seems to me it would be better to get rid of these modes altogether and use the Tandy-style ones (possibly renamed back to M_CGA2 and M_CGA4) so that CGA bugs need only be fixed once to be fixed on for all machine= settings.