My friend is a Samus main, and I've noticed something about fighting Samus. Due to her Floaty/heavy weight, she has pretty good control over the way you can throw her. I have difficulty finding the best follow-up, and the timing on D-throwing her into a knee is pretty hard, although I know it can be done (depending on DI). I have been experimenting with down-throw > nair, or to mix it up f-throw or b-throw and followup, depending on the DI. However, I haven't found an efficient way to follow up that doesn't look sloppy. It's normally just an improvision off of her DI.