Top 5: Gamecube, it has unique non-first party titles and some of the ports are a lot better there, also i grew with goated licensed games there (Over the edge)
PSX: Had a pirated one, grew with it, every Sunday of Tianguis seeing those hanging PSX bags was like chrismas every week
Nintendo DS: IDK if it counts since i am playing in an actual DSi, but no wonder it managed to beat the PSP in sales, the damn thing was a machine when properly used (It sadly fell for the shovelware trap, so buying games was a minefield)
J2me: Remember those games in your dad's phone that logically weren't as good as say GBA? i had a Nokia Xpressmusic , Ancient Empires, Gameloft ports, Pizza Manager, Orcs and Elves II... is a shame finding roms is a risk due to most pages being trojan stables
PSP: Though i will disrespect the best of the best? PPSSPP in my phone plus a joystick has made long trips outside home far more relaxing, while i had an actual PSP growing up, sadly time is unforgiving and eventually it perished, but now with the modern technology and... preservation ;) now i have access to those games i enjoyed, but also can play the ones i missed