The prospect rankings vs real difference in talent is negligible when you are talking top 25. Jo Adel was #1 a few years ago and Dylan Carlson was 15-20 and I would much rather have had Carlson.. Kelenic was ranked #1 and not doing so hot yet... I can go on and on.
Thomas is young, he didn't do well in his first go at the majors, it happens. Thomas has good historic perifials and fills a position of need for us.
To rephrase, I would be happy with Thomas for Moreno. I don't think, and you seem to agree, we would get a pitching spec worth a s*** as well.
I would ultimatley LOVE Varsho... Don't see it happening from the D-Backs side, but that would be sweet.