I finally got around to watching the game on my DVR.
My observations: Croft appears to be more athletic, and definitely a better runner. but there were a couple of times it looked like he had a chance to cut upfield, and he angled for the sidelines. I suppose he could be coached to go out-of-bounds, but it looked to me as if he was trying to avoid contact. As a passer, he mainly attempted shorter throws. I remember one deep attempt at best. Hard to get a reading on his arm strength from what little we saw.
Rhoda did seem to have a quicker release and a little more zip on his passes. he overthrew several balls, so seems to have good arm strength, but the touch left something to be desired - most clearly on the INT in the end zone. Rhoda is clearly not a runner. I don't think he every tried to keep the ball on a run option.
I guess if I had to choose, Rhoda might be the better short-term candidate, but I think Croft might be the better long-term choice based on athletic ability and running threat.