Oo i don't see the problem with it I love this game even more than i did at the good old GB Mono times.
and i don't even notice the Mii when i play the game cuz i have to concentrate on what happens on the 3D screen ... what speed do you play at that you notice it anyways XD
only thing which i think is weird are the acievements, I allways thaught i am more or less "good" in this game but hell oO when i got my first million points i was like "hell yeah I am the best" than i look into the acievements only to see that i am missing two in the endless game (no stop at line 150) the 5 and 10 million ... totaly insane, for the 1 million it took me half an hour so for 10 it would be 5 hours ... ok i start mostly at 1 just rarely on 15 still i try to do as much "Tetris" as possible (clearing 4 rows at once).
And there are some acievements i do not understand and some of the party games are not to my liking but there are sooooo much different modes ... for me only the normal one would have been enough XD
Only thing i REALLY do not like is when you do Battle with items that these items are totaly stupid ... changing the field is like instand win, just make the worst possible field and change shortly before you would die, if the opponent does not have the same item to switch back its insta win, and that dust ... even thaught its a good idea i allways get dizzy cuz you have to blow like hell -.- could have been more sensible.
P.S. is it just me or is online broken ? first try online after like 10 minutes i got an error message without getting to play, second try same, third try i got an opponent than error and after that every new try didn't even show me that "training" screen and just got me an error message instandly -.-V