I posted about it earlier, but here's two examples of gray colored battle droids which (I believe, anyway) look more mechanical an thus embody the nature-technology conflict that's present in a lot of Star Wars and could go some way to making them a little more intimidating...

Also, I don't know about anyone else, but I personally like the idea of all Old Republic Jedi using blue sabers.

Okay, now I'm just having fun but here's Maul-Grievous. It'd certainly give Maul more purpose, but might be damn difficult to actually get in there.