Alright then... Uh... CPMC-tan should look like the offspring of Cirno and Rin Satsuki, wearing glasses and, um, a labcoat, I guess. And yes, a dunce cap.
TARC-tan should look like Reimu, if she was a junkie going cold turkey. If that helps.
UGW-tan... A maid. Dressed as a mafia don. Using Unlimited Blade Works.
Also, this may seem like a kind of selfish suggestion (to be perfectly honest, it is), but... If you're really trying to think of what to draw, there's always Lunablade... That is, if you want to. You don't have to. Just... A suggestion, that's all.