I can definitely see his less is more issue because playing online with more people can be frustrating especially if you don't know the people you are playing with and can't talk to them while playing. On the other hand, playing in person the items from others in the room can add to the enjoyment.
I disagree about the Wii Wheel though. I find it fun to play with. It may not be quite as much fun as tilt steering in Excite Truck, but still more fun than tilting a half-inch lever. I've only played with the wheel so far, but I could see how the other methods may be more precise.
The times for some unlockables is insane, at least to me at the moment. Maybe I can improve drastically when I get used to the wheel or switch to a Wavebird and beat them. I wish they'd included the DS challenge mode or whatever it was called. That was more fun than simply beating a ghost.
On another note, I like the addition of and to the tournament mode, but why couldn't they have included stuff like that offline.