Wow, let me think back and remember what I thought of it...it's been over a couple years now?
It was fun, while a few parts did seem a little drawn out. It wasn't worth replaying since I've never really been that interested in completing my sticker collection. It was a neat addition and definitely gave SSBB a good asset when it was first put out on the market. In the short run I think it was a good thing they included it, but in the long run I believe it would have been wiser to instead focus on a killer mulitplayer mode, with much better WiFi. So much energy was put into basically making
two games that it took away from what the main game could have been.
Definitely things to keep in mind for SSB4.
Thinking about it, I wonder if they made a Super Smash Bros Adventure format game. Imagine how fun it would be to play as Link, Samus and Mario in one game where they don't fight but rather work against a common enemy like Tabuu.
And like LOZ, there would be puzzles that only a certain character can solve. That would be interesting to see Captain Falcon solve a Zelda-like puzzle.
SSBA - Super Smash Bros Adventure? That could be pretty cool.