Not really a Smash Bros fan anyway, but I'd play with the trainer as much as anyone else, I imagine.
The real question is, who are we *losing* to make room? Obviously not Mario or Link, but if she replaced someone more iconic like Peach or Samus I'd be pissed.
The Wii fit trainer does not belong in a brawling game because they are not a "character". There's no definition or iconic history. There's just... instructional blah.
It would be like a new X-men movie with a some girl who's called an X-men but who just kind of hangs around but doesn't do anything, has no face and is just there. BLAH. Or like a Transformers movie where some stupid, boring kid takes away Robots smashing each other screen time to yell at the robots for stomping in his garden. Oh wait. You're all just a bunch of Michael Bay fans.
I would argue that Wii Fit Trainer is iconic. Just because she hasn't been around as long doesn't make her any less of a Nintendo icon, it just makes her a new one.
If you were to ask the average person (please note, not "average gamer") about the Wii, the Wii Fit series is likely to be brought up. Perhaps not the character, but then again, was that not the situation with Roy and Marth in Melee? Many western gamers-particularly younger ones-had never heard of either of those characters. If they were extra-nerdy, they may have heard about the Fire Emblem series but never played the games, since none of the Fire Emblem games had had western release at that time (please correct me if I am wrong.)
The point is, they are bringing in a character from a modern release. While not as widely known or recognizable as Mario or Link, this has never stopped Nintendo from character inclusion in previous Smash Bros. titles.
God this whole thing reeks of gimmick! When she said that the Wii fit drone and the animal crossing dude were added, but Nintendo wants to make it clear they weren't last minute cheap gimmicks, I laughed so hard! Of course its a cheap gimmick. The Wii fit drone is NOT a character; she's the distinct lack of a character. She is a non-judgmental friendly and approachable representation of the player. She has no personality or motivation beyond that which the player gives her. Its like throwing in a Perfect Dark meat sim as a character and claiming it wasn't cheap nostalgia.
The animal crossing dude I have less to say about because I never played the games. Don't know him, never will. But I do know he's not a classic character. So no idea why he's in such a...respected...title.
I'd rather see one of the TMNT, or Princess Ruto. Hell, grab the cyber commando from Contra or Joana Dark herself! Now that'd be a fan-boys dream. Zero-suit Samaus vs. Joana Dark in a brawl. And Leonardo vs. Link.
Hell, grab Jessica f-ing Rabbit and have her bonk things on the head with a cartoon hammer!
The Wii-fit Trainer was real?! I thought it was a joke this whole time. Someone please tell me it's actually a joke?