Dragon Quest XI S is an incredible game and the pinnacle of the entire series thus far, imo. It has a truly loveable cast of characters and a great story, both overall and in the individual vignettes, so much so that I got really into the nitty-gritty deep story/design analysis stuff for a good while. There's also plenty of sidequests, opportunities for grinding/collecting, and horse-racing and gambling mini-games! The graphics are gorgeous, especially in the cinematic cutscenes, but you can also play through the entire game with retro pixel graphics if you so desire. And if you like doing challenge runs, there's a good few Draconian Quests to give you as much or as little added difficulty as you like!
I also had a blast with Dragon Quest Builders, which combines their usual RPG elements with sandblox building and tower defense, with action-based combat instead of the standard turn-based. It also has a sequel that I've pretty much only heard good things about!
I've yet to play Dragon Quest Treasures or Dragon Quest Monsters: The Dark Prince, but I've played a lot of Dragon Quest games and never been let down before.
I'd also like to second the recommendation for the Rune Factory games on the Switch! They're a combination of action-based fantasy RPGs, farming/life sims, a bit of monster-collecting, and of course, a fishing minigame. Or, as I like to call it, "everything I could ever ask for in one game". The mechanics can get pretty deep
(the forging/crafting is too complicated for me to fully understand if I'm being honest) and they also have lots of room for grinding, if that's your thing.
Rune Factory 5 admittedly runs poorly and has a few minor bugs, but there's something about the game that's just super comforting to me, and it's still my favorite of the series that I've played. Notably it has more relaxed pacing
(in case you're like me and get stressed out by how short days can feel in farming sims, although this does mean that you can progress through the story a lot faster than normal as well) and is the first Rune Factory game with same-gender relationships! It also features more linear dungeons than in RF4, which I know some people missed, but was honestly a plus for me because it meant I didn't have to continually pause my game to squint at dungeon maps online.
And I've still found plenty of little secret spots!
Rune Factory 4 Special is a very safe bet for newcomers to the series—it works smoothly and has the most content of the RF titles currently on the Switch, although romance events (and most other town events) in this game are random, so if the RNG doesn't like you, you might be waiting a while before you can romance your favorite character(s).
I'm only part of the way through with RF3 Special, but I'm enjoying it as well! However, unlike in RF4/RF5, you can only play as a male protagonist and romance bachelorettes, and the maps feel more straightforward as in RF5.
Also unlike later titles, crops die at the start of new seasons. I found this out the hard way. orz