I would suggest going back to the classics
Get an online subscription and play through SNES Mario, Zelda and Metroid. I mean, these are literally some of the greatest games ever made
Outside of that
Obra Dinn
I played them when I was a kid. Going back to them, not so much.
Thanks for the recs all, my mate has recommended Hades a lot, but he also thinks that it'll be announced for Xbox and PS at the Game Awards, and if so Xbox would be my preferred platform. I've got Obra Dinn on my Xbox already and looking forward to starting it once I've finished Greedfall.
As for games I like my favourites are stuff like Daggerfall, The Witness, Link to the Past, Sea of Thieves, Celeste, Illusion of Time, Quake 3, PGR2/Forza Horizon 4... I like most things really, aside from the Ubisoft Ur-game stuff. I don't know what it is about the Nintendo games I've played on Switch but I really struggled to get into them and either gave up or chunks of it felt like a chore. Baba is You was good up to the point I hit a brick wall! Merchants of Kaidan was a decent sale title, but kind of shallow in the long run and that UI bug was a real PITA.
Thanks to sales I've got Skyrim and Ni No Kuni on the Switch. The former I know I'll play because I only played through it once in original release and wanted to return to it, the latter was an £8.00 shot in the dark. Oh and also got Transistor cheap, speaking of Hades and all.