SMASH 150 - 020 - WALUIGI

Waluigi is a bit of a fan fovourite and has the honour of appearing as an assist trophy twice, which is a pretty notable acknowledgement but it means his future could go one of two ways: The Little Mac route where he eventually gets promoted to full character or the alternative route where he stays as an assist forever because he doesn't really deserve to be playable and this is pretty high recognition to begin with.

Waluigi in Smash
I like Waluigi and I think he would be fun to play as but I must reiterate that I don't think he deserves it. He hasn't really offered much to the Mario series in general, has never broken out of the spin-off circuit and only really exists as a contrived player 2.

Of course, the same couple be said of Luigi's original appearance since he was a literal palette swap, it was only due to Nintendo themselves putting in the effort to develop him that he became the character we know today.
However, Waluigi was not created by Nintendo (right?) and did not originate in a main series game so Nintendo have no real responsibility to take him any further.

But he's an assist trophy, and his popularity has been recognised on more than one occasion. That's important, and it would tie a neat bow around the Mario/Wario/Brothers/Cousins(!?!) group. It would seem odd, though, for Waluigi - a character who is closely associated with Wario and only exists to serve as a partner for Wario - to appear as a member of the Mario series. And it would be hard to cast him as a Wario character since he has never appeared in a Wario game and Wario himself is distinguished by having an alternate costume, which Waluigi so far does not have!

Waluigi in the Mario series
People have been clamouring for years to see Waluigi transition into a main Mario game and so far the costume in Super Mario Odyssey is the closest thing we've got. Other people want to see him get his very own game!
It's a stretch but that would certainly help his chances of a playable Smash appearance. I kind of like the idea that Waluigi is stuck in this purgatory of spin-off games because he was created as such a contrivance but I wouldn't rule out the possibility of a starring role.

But there's a problem. How do you make a game about Waluigi? Some have tried, but I have yet to see anything convincing. I think for Nintendo to consider making a game about Waluigi, it has to be a game that could only star him. It has to actually play off his personality! If your game could swap out the main character for Mario, Wario or Luigi then what's the point of casting Waluigi? Why not just make it a Mario game, right?

I do have an idea for a Waluigi game, one that I don't think would be suitable for any of the other plumbers (though I'm not going to go into it now) and that's the point. It could only be about Waluigi and I think that's the only way he'll get his own game.