Just some initial thoughts here, I'll write more later...
First of all, yeah - I was a little disappointed that they didn't have any sort of goodbye/good luck exchange, and I would have felt that way whether I shipped Dinbo or not. After everything they've been through this season, it seemed a completely reasonable expectation. But instead of fretting about it, I feel that the writers made an intentional choice to show the viewers that their story isn't over. There was no need for "goodbye" because they're going to be in and out of each other's lives so much over the next season(s). Like, yeah - he's got a little cabin all his own on Nevarro, but he also has a home on Mandalore and a home on Tatooine whenever he wants to be there with his friends. We'll get the payoff with that bottle of wine next season.
Din's story with Mandalore is far from over, so there was no need to conclude it. Grogu sensing the Mythosaur and it sensing him in return is all the proof you need for that. Grogu is a Mandalorian now and learning the bounty hunter trade just like Boba did from his father (and still practicing his Force techniques). Din is working as an independent contractor for the Republic Carson Teva, rooting out any Imperial threats in the Outer Rim, which makes him the first line of defense for his people. He's doing what he knows, but he's doing it for two purposes: raising his son as a Mandalorian and protecting his home. His pledge to Bo-Katan still stands. She is the Mand'alor, which means by creed that when she calls, he comes (and maybe vice versa since I believe she feels equally loyal to him).
I knew from the beginning that this was going to be a slooooow burn romance if they ever fully develop it, but Din is still her first knight and she is still his liege lady. That didn't change. In the meantime, we just do what we always do in-between seasons: write fanfictions, create artwork, compose meta, and edit music videos.
That cabin on the outskirts of town though...juicy stuff is gonna be happening there on ao3.