These look great! Glad to see OG Macross figures getting some attention. Max's head does look larger than the others if you are going for a more realistic look. If you are aiming for a more anime look then the larger head looks fine but you may need to lengthen the legs a bit.
Agreed, the old Imai 1/12 basketball player Roy figure looks way too disproportionate to the others in the series and still bugs me.