Well.
I'm sarcastic, shake things up, mess around with NPC's in various ways because I get my kicks.
As for tough choices: I do whatever is pragmatic above all. Logical, regardless of feelings. Even so .. I do have a code and a line I won't ever cross in-game. Like betraying allies loyal to you, even if they're annoying. Or killing of loose ends in a mission(witnesses, or might know something but say they don't) I'd usually do, yes, but not if they're kids or woman and no threat to me. That's beneath me as a roleplayer. I could never go full on evil to the point of being completely dishonorable or heartless because it sickens me. I may be cold and apathetic seeming in games, but I play it honorably enough.
I don't kick puppies or give everyone hugs. I go by some moral code of my own, which tends to be outside whatever is expected in-game(Black and White is too simplistic and dull, I'll break the system). Otherwise if the code isn't crossed then my sole focus will be self benefit of my character.(Or my power base, assuming I have one)
Overall I'd say I'm pretty grey. Chaotic Neutral, or True Neutral? I gravitate around.
In star wars I played honorable sith's and grey jedi's. Tales from Borderlands and other Telltale games like Game of Thrones I ended up more neutral and towards pragmatism, and I let anyone join me who will aid me in any way unless they've proven untrustworthy to me. In Alpha Protocol I joined the bad guy at the end only to betray him and take over his secret organization network, having built up my power base prior so instead of him manipulating me into his hands he fell into mine. Then I had ultimate control to make things better from the corrupt organizations beforehand. Or Mass Effect where I am also pragmatic and more of a Paragade or Renegon(mixed) rather than Paragon(good moral man) or Renegade(controlling jerk, with a temper) but both can have a level of pragmatism. Ect. I love multiple choice roleplay games for the freedom of choice it presents, even if the games end up more often than not very linear either way.
But I also observe my own gameplay and even others gameplay on YouTube often for example ... to analyze what they did and their reasoning's because it fascinates me.