My pick would be Kimberly Guilfoyle. Trump prefers women who are attractive and obsequiously loyal, and she checks those boxes more strongly than MTG boxes. Plus she ticks the nepotism/incest boxes in Trump's psyche.

I also think that when support for his run for the presidency flags or sags, he will announce a choice for VP early, just to get back in the limelight and prove how "serious" his run is, and how he can break norms and get away with it.