In working through my Indie GOTY list, I had a few I couldn't put on the final list, but I enjoyed my time playing and thought they were worth a note.
One of the best looking games I've seen in ages, Cuphead is a highly polished platformers/shooter that looks like it was pulled directly out of Steamboat Willie. It's an incredible achievement, and probably would have been on my list of Indie GOTY if the 3 I chose didn't make it in the calendar year.
Another - out of nowhere title, this little RPG based in a world of golf also pushed me to play to completion. It's basically your typical 16-bit RPG, but replacing swords and and magic with clubs and golf balls. You still get all the quests and story telling and leveling, but it's a totally unique and silly wrapper that is tons of fun (and it's another Switch title).
Children of Zodiarcs
Much like TINY METAL, CoZ is attempting to fill a specific gap - this one is shaped like Final Fantasy Tactics, but it does have a few tweaks of it's own. The inclusion of deck building and dice to add to the RNG is a fun twist. The only thing is that the story line never really captured me, so it's a game where the game play pulls you forward.
You are in charge of an ailing ludus where you must acquire, train and equip gladiators. The game also has a simulation aspect where you must manage your income and properly outfit your ludus to further your gladiators skills. It's got a cool pixel-art look and a wonderful soundtrack that really makes the experience.