I guess at the end of the day what feels fillery is going to be subjective, I am also somebody whose favourite part of OG FFVII is post Midgar up to the Northern Crater, so Im going to be more amenable to what Rebirth expands on. There hasnt been anything so far where Im thinking okay, wrap it up like at a few points in Remake but I can see that going the other way for someone else.
What I will say about Rebirth is, it definitely does a much better job of handling its side content than XVI. Both in terms of the quality of the content and keeping it to the side. Rebirth seems pretty tailored for people who want to mainline it as well as those who want to explore, while XVI not only very visibly surfaces every side quest it puts major story and character beats behind them. Also XVIs exploration is not good and I like Rebirths a good amount.
I just decided to change this sig.
Blaaaaaaargh
azuarc