I don't think I ever realized it before, but Baccarin's Anna from the V remake was a very Servalan-like character. And since Anna was the only non-awful thing about that show, it might be nice to see her do the same thing in the context of a better series.
Still, the similarity strikes me as a reason not to cast Baccarin in the role, or at least a reason why she might not agree if it were offered. It would be redoing something she's already done, and she might feel that didn't sufficiently challenge her or advance her career.
I honestly completely forgot about V until someone mentioned it here. I thought of Morena completely independently from that. Probably spurred by her short Servelan-like 'do.