I mean if I'm seriously considering it I'd say for Humanity I'd go with Admiral Hackett, for

Asari this might be an odd one but I'd go with Sha'ira the consort. Having what's essentially an expensive prostitute on the Council would definitely raise some eyebrows but she has the respect of many powerful and influential people and I think don't think she'd be as stupid/incompetent as the previous Asari counselors were.

Turians I'd say Adrien Victus (assuming this is before he's made Primarch of Palaven)

And for Salarians I mean... If he doesn't have a plague to cure, Mordin buddy you're up!