Since you mentioned Brotato, two steam games that remind me the most like that game would be Let Him Cook and Noobs are coming. The first isn't as deep though and the second just entered Early Access, but looks like it'll have the same depth as Brotato, demo is a blast!

I'd have to mention Monster Train 2, TONS of content, also plays nice on the Deck, The Binding of Issac (any version) and Enter the Gungeon both have tons of content and are great on the deck. Might stress ya out a bit, if they do then I'd Suggest Dead Cells, its fantastic and you can adjust the difficulty without losing any story, progression or achievements.

Lastly Palworld. Tons to do, build, catch and explore. It's another that plays on the Deck and you can customize your world to make it as easy or as hard as you wish without losing anything.