I went with a Rogue Dual Dagger Female Cousland, because I'm boring and tend to pick human.

My ideal 'get stuff done' party pretty much always had Alistair (who I romanced and became Queen with), a Mage and usually a second ranged character, typically Leliana or the other Mage. I was playing on Casual though, so party composition wasn't so important and I brought along whoever was best for approval or banter. Zevran didn't get much of a look-in though, due to the double-up of roles.