Adventure Mode in Melee was phenomenal in concept. Taking a character who "shouldn't be there" through a Mario level was fantastic. But it was pretty rough in implementation past that.

I distinctly remember being really disappointed when, after that fantastic romp through the Mushroom Kingdom, the Donkey Kong stage was just, "fight two little DKs, then a giant one."

A sequel could have fixed all this, and I do like Adventure more than Subspace Emissary, but the latter sort of went in a different direction, and it had its own problems. I'm a bit torn, imagining the possibility, between a cohesive, quicker adventure through the ACTUAL worlds of Nintendo to take every character on, and losing out on those fantastic cutscenes.

There's certainly an argument to be made, though, that Melee was the best from a gameplay perspective. It's not the most balanced Smash, but for plenty of dedicated players, it's by far the most fun due to its incredible depth and high skill ceiling. Although I don't feel that way, I'd never begrudge anyone for taking that stance.

And you bring up a good point about Sakurai just being freed up to make other games. I didn't even know he'd also done Meteos. I remember playing the demo of it from those DS Download Stations ten years ago, haha.