This reminds me of the second half of the Hyperion cantos by Dan Simmons

I <3 the sci-fi gods like Herbert, Heinlein and Asimov, and they all had great sci-fi takes on religion ... but Hyperion has THE best take on sci-fi religions IMHO.

It seems that is the first in his series but is that a good one to start after Dune? I’m on the last book there and, man, the pacing is questionable.

You mean the Endymion books, or Fall of Hyperion? I'm rereading the latter right now..

For the religion bits, if I remember correctly, it was a bit of Hyperion but mostly the Endymion books, which are the latter half of the cantos.