Funny this thread asks this question, as i have been thinking about this in recent days. for me, ultimate took my vote. I've loved smash to death since n64, but even though ultimate gives me every character, tons of stages and an amazing soundtrack, i feel the game is taking it's self to seriously with trying to be a competitive fighter with all the attention to frame data, techs and combo ability, and lesser on the ridiculous fun factor that we fell in love with during the n64 through brawl era.
There's nothing wrong with it going this direction, but as a fighting game fan, I want my streetfighter, tekken, dbz to feel different from smash. I also really miss things like break the targets, board the platforms, home run contest, smash run etc. even all-star mode got gimped.

Really? Because I’ve said a lot of good things about it in this forum, as have others.

It’s the only game in the franchise that isn’t obsolete due to all other games being eclipsed by Ultimate, but not Brawl due to its superior single player mode.

It is the Smash game that really put the franchise on the map ; as while the earlier games weren’t bad, they amounted to little more than a Nintendo license novelty fighting franchise (outside of the hipster gamecube fanboys). To this day Brawl maintains the highest success both critically and commercially; although it will eventually fall to 2nd commercially, its healthy critical lead over Ultimate won’t be surpassed.

Ultimate and Brawl are both at 93 on Metacritic, and Brawl is only 0.73% ahead of Ultimate on GameRankings. How in the world is that a "healthy" critical lead?

3DS / Wii U now that Ultimate on theSwitch basically combines the full roster and portability of both versions. I still play OG Smash from time to time, its a great pick up and play party game and I still enjoy its simplicity compared to all the stuff that's been crammed into later versions.

Ehhrm...

Brawl introduced 3rd party characters, Solid Snake and Sonic first appeared in Brawl.

Easily Smash for Wii U. Like the rest of the Wii U library it might as well have not existed to be honest, it's completely invalidated by Ultimate.
Though i'm thankful that it was that final push I needed to get into Melee.

Yeah, but that was more of a test, Wii U/3DS very vastly expanded on this by adding tons of third party characters assist trophies and Mii costumes.

Besides, my listing is more about what defines each of those parts; Snake and Sonic are not the  thing that sets Brawl apart, it's it's Story mode that does.

I hate Melee so I wanna say Melee but honestly probably the original. Sure it started the franchise but that doesn’t mean it’s relevent.

I find it kind of strange that Melee is held so high since it seems the competetive scene is all about exploits in that game.

The cult of pretentious Gamecube hipsters. They skulk around the Nintendo fanbase like Smeagol.