The only one that springs to mind is #1 - Garwin Sanford, who has the distinction of bagging both Sam Carter and Elizabeth Weir in two separate Staragate series. :D

He played Narim SG-1 and Elizabeth's Earthside boyfriend Simon Wallis in SGA.

Oh, and I can't think of #3's name, but isn't the chick who played the head Tollan woman in Between Two Fires and Shades of Grey?