I did notice in Ryan's speech and during Trump's speech that neither one of them gave any credit or thanks whatsoever for Cruz campaigning for Pence, and for those down ballot. IMHO Cruz helped is win probably more than most and they've already eliminated him from the political scene. Instead they thanked people like Christie and Preibus! Yes, we still have a lot of work to do!!
Well, in fairness to both of them, there other elected Republicans who helped Trump as well. Christie was actually part of Trump's team, and Priebus was head of the RNC, so I can see why they were singled out.
I know all the folks who want to see Cruz run for President at some point, but there's no guarantee he'd ever win. A 30 year, hard core judicial conservative on the Supreme Court would be absolutely huge. But I think even Cruz himself would prefer an elective office, so I don't think there's much of a chance of that happening.