I was looking at getting some roguelikes / lites (already have ToME, CoQ), unfortunately Cataclysm DDA is not on sale.
Krone Hotel at 90% off looks like a decent choice too. Then there’s Jupiter Hell, which I recently stumbled upon and looks great too.
I’d also like to get some of the FF games, though I’ve played VI, VII, IX and a bit of XII, it would be nice to revisit some of the older ones I haven’t played almost since the PSX era.
Might I suggest Neverwinter Nights as well. The online community is very robust and it offers an experience unlike any other game that I’ve played to date. It’s text based and most of the populated servers are roleplay servers. This means tons of typing and would probably be better played on PC. But they do have a mobile version so it may run decent on steam deck. It’s $5 and worth that anyhow.