Honestly, I'm surprised no one's come up with this one yet -
A Massassi Sith.
Seriously, it's got "WIN" written all over it!
now for a republic character..... hrm.....
*consults Wookiepedia*
How about a Yuzzem for a trooper, and a Verpine for a Smuggler? The Yuzzem's are heavily similir in a majority of factors to the Wookiee, and the Verpine's're a heavily-tech-savvy, yet relatively territorial race by nature, making them, IMO, a relatively good idea for the Smuggler, what does everyone else think?
And also, for those saying Droid, what type? Assassin, Protocol, Agromech, Construction, what? Honestly, I see a new, long-derived descendant of the Hunter-Killer Protocol Droid line becoming a character for like, the NFU's, but that also coincided with the HK-51's that'll be a new companion.... Maybe the New HK-whatever droid is the controller, and thinks himself far superior to his/her (based on programming) ancestor? IDK, what do you all think?