I don't mean to question your decision, but I find it odd that you mentioned only playing Brawl 2 or 3 times, right before saying you enjoy games with more "franchise accurate" experiences and less mindless fighting. Because that sounds exactly like what Brawl's Subspace Emissary mode is! A fleshed out campaign mode full of great scenes mixing the best Nintendo characters interacting with each other to defeat a common threat.
It might not be the absolute best execution-wise, but if you really didn't play it, you really might want to check it out as it sounds right up your alley
I personally like great party games, which Smash most definitely is. In fact, I bet I would love it even if it wasn't Nintendo characters fighting. My friends and I have tons of fun playing it and that's my main purchase reason. So, if you're not a big fan of mindless party games or prefer more fleshed out single player experiences, I can totally see why you'd feel Smash isn't for you, and worry about all the fan service sucking you in for a game you won't actually like.