There's been some nice QOL things they seem to enjoy continuing as the series goes on. Things like the phasing out of HMs, options to add a newly caught Pokemon to your party, quicker PC management, continuing repels, changing how move tutors work, and just easier menuing, all of which I hope get brought over to BDSP.
As for specific things I've got in mind...
Move Tutors are a big one for me personally. Why did we have to check a separate board to see how many shards of what type we need for each move when tutoring? Why did we need to select a Pokemon to see what moves it can learn, and select a move just to be told we don't have enough shards?
Why did we have a separate Treasures bag in the Underground so we have to remember to transfer them over to our actual bag? They serve zero purpose in the Treasures bag.
Why did we have to speak to certain people to change how we appear to others in multiplayer?
That being said, the Poketch is pretty much a QOL machine and I'm interested in not only how it'll function with the game no longer having 2 screens, but how it can introduce new and interesting QOL changes into BDSP. We had a portable PC box in SWSH, what's stopping them from giving us a PC app on our Poketch to switch things out on the fly? That sounds sweet!