I think there's way too many costumes for Great Saiyaman where they would have to make two, maybe even three, versions. One with the helmet, one with the white bandanna and sunglasses, and another in Super Saiyan form. I can't imagine they would make all of that for one version without eliminating quite a lot of the costume.
All they need to do is include 4 heads (Helmet/ Bandana/ Regular hair/ SS hair) and make the cape removable like Piccolo's was - whats hard about that? Plus, based on the previous releases, looks like they tend to choose the first look for a character (see Trunks, Android 18), even if they had different clothes or appearances)