Ah, that explains things. You get a deeper impression if you actually have the game, because that way you can compare what changed and what didn't.
As for sticking with Melee, you could very well do that. But I gotta admit, after seven years, the game has run its course. Brawl although similar, is chock full of extra features and other gizmos that would help with the longevity of the game. I guess you could say that it's like an "expansion pack" of some sort.