I second that really. Having your own characters is infinitely more interesting then just trying to shoehorn canon characters in. You can do alot more with your own then having to adhere to canon personalities and such. There's more then one Milfy Justicar out there then just Samara I'd wager.
Regardless, I've followed your progress for a while and I'm quite impressed by the strides you made since the early versions. Definitely one of the more interesting projects out there I have to say. That being said, have you ever considered an alternate skin system for Tali? Different outfits or maybe alternate characters entirely, unlocked through gameplay?
Though given the animations, it'd probably get absurd real fast work and filesize wise wouldn't it?