Mario Kart gets more party-like with each new game...doesn't mean the hardcore can't make something of it.
From what I see every day, I like. I like the crazy stages, the Subspace mode, additional items, whatever. If it's the Final Smashes that are just too much for some people, you can turn those off...you can do whatever you want in this game.
I simply fail to see how this game can fail...simply by the sheer amount of customization available.