Do you have an existing Steam Library? Tons of games are verified on the deck. Anything with controller support is great.
If you haven’t played them: brotato, Hades, and Stardew Valley are all perfect on the deck, off the top of my head
There’s also Old Time Hockey. Looks like a lot of fun, although I’ve never tried it
Super Mario Odyssey - 1 UP Girl is a phenomenal song, and the rest of the soundtrack rocks as well. Bonus points for every track having an 8-bit version
Final Fantasy IV - My first SNES game. I still have that entire OST burned into my mind. The first time I heard the full orchestral version of the FF theme (I had played FF1 previously) blew me away
Outer Wilds - Better when heard in-game. I still tear up hearing certain pieces
Mega Man X2 - SNES era Capcom music at its best
The Great Ace Attorney - Really the whole series, but I think this one is my favourite. Capcom has great composers
In the expansion, I accidentally discovered what happens when you put your lantern down and walk away… That one was easily the biggest suprise out of the whole experience!
Final fantasy pixel remasters!
I just recently watched Poker Face, and it was amazing. I also happened to watch 6 seasons of Columbo in the past year, and Poker Face is Rian Johnson’s (Knives Out) tribute to that show. If you were ever a fan, you should check it out.