This game was the sole reason I bought a Wii U and while I had about as much fun with it as I could have, you aren't going to miss out on anything special that can't be found in Smash Bros. Ultimate.

As for the Wii U itself? This was the sole game I owned for the system as I owned the lesser white version of the console which was so lacking in memory that installing much else other than Smash that wasn't a demo was pushing the limits of what it could cope with. Buyer's remorse to the max.