The short version of the Unix philosophy is basically, “Do one thing, and do it well”.
Michelle Rodriguez basically plays the same basic character in every movie: tough girl / tomboy who doesn’t take crap from anyone, usually wears a tank top, and dies about as often as Sean Bean.
And it’s not a bad thing.
While I haven’t seen every film she’s done, I have seen a lot of them, and she gives a stellar performance every time.
So she may play the “same character” over and over, but she does it very well.
She was in Halo 2! I forgot about that. I think she was already big but just wanted to do it. On the Resident Evil commentary she talked about how she loved Half Life and smashing zombies with a crowbar so she probably was a fan of Halo as well.