Side question: how many people RP versions of themselves, whether in terms of personality or areas of interest (e.g. RL businesspeople doing trade and industry, etc.)?
I do, pretty much. If I RP someone evil and/or badass I always end up feelin bad in the end
I never had this problem, atl not in ME2. The problem there though is that 100% renegade is considered by the developers to be bad-ass, ruthless and merciless to one's foes. In reality, 100% renegade score - accepting the renegade option all the time - is just the recipe for a total asshole.
I had no problems maxing out my renegade score playing the role of the utterly merciless ruthless 'mission done at all cost' type, but I also ended with half of the paragon meter decked out due to accepting options that were logical and expected, for example, in regard to crew-members and companions and their issues.
As such, this is just an example that it's possible to be 'evil' or darker than your average hero, without being an utter, unsensitive prick as well.
And as for the original question... the only toon of mine simmilar to myself in RL was BB, and that was the original way of thinking, reasoning and some facets of personality. This morphed over time and now only a few parts of him retains hints of 'me' and how I might solve stuff/think. As for the others, they are mostly stand-alone works with little or no connections.