Which mini/classic console is best to mod to play NES, SNES, Sega Genesis?

I own all the official classic/mini re-release consoles (NES Classic, SNES Classic, Sega Genesis, and PlayStation).

Which system would be the best to mod for either of these two options:

1. Playing NES, SNES, Sega Genesis ROMs?

2. Playing NES, SNES, Sega Genesis, and Playstation ROMs?

The reason for option 2 is that I don’t care much about Playstation (never grew up playing it) but I’m interested in trying a little. In that case, would it be better to just mod my PlayStation Classic to just play all PlayStation games and mod one of the other consoles to play the 16-bit systems games?

What would be the best up-to-date guide for doing this? I‘ve never done this before.

Thanks!