I had a N3DS, it was my first handheld and it was great! Really good selection of games. My most played were Monster Hunter Generations (which was my introduction to the series) and Fantasy Life - one of my absolute faves, a charming and colorful fantasy adventure with life sim elements. The story is a bit meh but the gameplay loop is incredibly satisfying and there’s nothing else quite like it. I’ve been replaying it on an emulator (rip Yuzu/Citra devs) recently and it’s still a blast.

Nothing quite like Hardspace: Shipbreaker, but farming games/life sims often fill this niche for me. The classic one to recommend is Stardew Valley, I also really like Graveyard Keeper, Slime Rancher and Fantasy Life (3ds, works well on emulators).

ARPGs (Diablo style, so kill stuff to get loot to get your numbers up to kill bigger stuff) can be nice zone out games too, I recommend Grim Dawn (going to get an expansion soon, quite complex), recently released Last Epoch (very enjoyable, but might want to hold off for a while if you want to play online - the servers are a mess right now), and Chronicon (most casual of these three, very cheap, colorful explosions across the screens).

Other games I’ve tagged as “Space Maintenance” : Planet Crafter (pretty chill number go up/building kind of game where you’re slowly making a planet livable), Deep Sixed (short roguelike, try to keep a ship together enough to get through the game, very hectic and no progression between runs so may not be what you’re looking for), Delta V Rings of Saturn (top down space mining).