Remember if you're a PC gamer, emulation is a great place to look for couch co-op since PC gaming seems to be rather averse to split screen unfortunately. There are a lot of extremely good split-screen games on PS2/Dolphin that will look and run significantly nicer on PC.

All the Persona numbered games are pretty much completely self contained, so you can jump in to any of them in any order (except the 2 persona 2s iirc)

I never hear anyone talk about this, but one of my favourite games as a kid was Metal Arms: Glitch in the System. It has such a unique tone, and I thought it was the peak of videogame graphics back in the day. I'm not sure if it's necessarily disliked, but I just never hear discussion about it.

Ayn Odin! Love this little thing, currently playing through Pokemon Radical Red romhack (it's hard as hell but I'm getting through it). This little device is honestly a beast.