Personally I'm a fan of order and though we preach freedom and liberty and all that..some of us now the truth of life, of reality. There is no true peace so long as ideas are allowed to float around that threaten one order. There are better ways to go about it than killing everyone that opposes..yes.
But I think the republic version of everything is a fairy tale fantasy of good. (which is why they have a cycle of falling to Imperial forces). I think sith overdo it to an extent but I prefer their overall order.
R Yeah I'd join the sith but not as sith as Imperial military, probably agent.