A little bit of colorization on the some standard inventory pics could go a long way to reducing those kind of errors..
http://i48.photobucket.com/albums/f2..._Colorized.jpg
I did this quick little test and just colorized parts of the Blaster icon, might be worth doing, this type of thing is quick and easy,.. not sure if the weapon textures would need to be recolored to match in game, but if this is just to give the 'inventory' graphics a bit more help for distinguishing between unique or otherwise 'valued' items from the 'basic' items, it's an easy fix.
Cheers!