I can't help thinking that Trump selecting Priebus as his Chief of Staff only helps Ryan - Priebus is reportedly a close friend and ally of Ryan, and the perception has to be that Trump wants to work with Ryan.
Why not force Ryan out and bring in a new speaker who isn't openly hostile to the idea of a border wall and other Trump initiatives? Trump certainly has the mandate to do this with allies in Congress.
This had to happen.
1) The debt ceiling. Who else could get the necessary votes together to make it happen?
2) The budget. As one person, Ryan knows more about the Federal budget than anyone else in Congress. There is FINALLY going to be budgets submitted ON TIME, and that would not happen without him.
3) He’s devoutly Catholic. Trumps tape bothered him. He got past it.