I can't believe nobody has mentioned Lois Bujold yet. But summing up Miles, or the whole Vorkosigan family, in a few quotes, is . . . difficult. Nevertheless, how about--

"When you choose an act, you choose the consequences of that act. Miles' theist mother stressed the corollary of this even more strongly: when you wished something to happen, you had damn well better choose the acts which would lead you there."