Not sure exactly what you had in mind, but in regards to Villainous characters, I've got that covered! As a semi-active RP'er, I find that I prefer to play villains and therefor find myself with far and few opportunities to do so without coming off as a grouch!
Imp Villains I play:
I can provide my main villain, Darth Martarus, as a powerful and elusive, sometimes eccentric and obsessed Sith Lord who tends to operate things from the shadows. Haven't done as much RP with him as I'd like to, and in regards to his personal status, he has recently acquired an Alderaanian estate which he converted into an Imperial Fortress and staging ground for whatever dark and twisted deeds he intends to inflict upon the Republic.
Second, I can provide the recently reassigned former General of the Sixteenth Legion, Imperial Tactician and military strategist, Verithian. While his current career is mostly on hiatus in terms of RP, I am always looking for ways to bring my Imperial officer back into the fold, red boots and long winded speeches and all!
Third, Aerilos, current employee of the Tretarkii Syndicate, bounty hunter and self proclaimed cyberneticist with an avid obsession of "perfecting himself through cybernetic augmentation." Often seen making attempts to push his cyber-gatchets on others, Aerilos is a true borg, determined to increase his personal killing efficiency to new heights and perhaps devastate the Republic in the process!
Rep Villains I play (less often, but looking to play Rep side more, if RP situations arise):
Captain Kelidren, jaded smuggler who lost it all in the invasion of Corellia. Sole inheritor of his parent's corporate dynasty 'Aurora Industries', Kelidren was betrayed by his parent's former employees after their death. Having liquidated the company and turned it into a petty smuggling ring on Nar Shadaa, Kelidren and his parent's former employees ended up indebted to a mysterious Hutt called 'The Broker'. After a nasty run in with a Sith, Kelidren has reformed his life and is now set to reclaim his inheritance and get revenge against the Republic, the Empire, and the Hutts for the tragedy that has befallen him. Currently building a small criminal organization, Kelidren will do whatever it takes to rise again and reclaim what he believes is rightfully his.
'Jedi' Val'thiron - under the guise of an avid student of the mysteries of the force, Val'thiron spends most of his time at study on Tython. However, his true intentions remain a secret to all but a select few. (Haven't really done much with Val'thiron, as it is very hard to get away with playing a fallen or corrupted Jedi, I have found - but my intention is to eventually evolve his character into a mass villain who betrays the Jedi and the Republic, falls to the dark side, yadda yadda, StarWars StarWars)
If any of the above characters interest people as a possible Villain in a story arc, feel free to contact me either here or in game!
