Yes, it would fix the issue and blank maps would add practically nothing to the download size as they would compress to virtually nothing. However I have made that suggestion before and it isn't going to happen. If the game is supposed to use the default effect maps if none are present with a skin then it is a bug for it to go as glossy as it does and hopefully that will get fixed.
Well, here's my take in a crude or unrefined form. Since most of the orphans were optimized for AH2 graphics then less is more. So a blank Normal would eliminate some of that "panel line overkill" we see since the older skins were using artistic effects to achieve the illusion of lighting and 3D. (Sorta.) And I think the default setting being turned down a hair might also help. Lower the Spec, Env, and Power levels some.
This is based purely on playing with stuff offline.
The Normal map is really screwing with the visuals on those orphans, which is too bad, because a lot of them are still viable with a little help until something "better" comes along.
![salute :salute](http://bbs.hitechcreations.com/smf/Smileys/default/salute.gif)