Well, this really is divisive, isn't it?
I'm surprised to see so many people saying they switched to non-motion controls and were really happy with it. I did for one match, and I found it to be very strange and much more difficult. But then I didn't change the sensitivity; I feel like it may have been more manageable had I turned it down a few notches.
I still find the motion controls a little awkward, and I can see why some people are inclined to want to turn them off, but I feel like it's still the superior option and my only choice is to simply keep practicing with it and get a feel for it.
Actually, I was a pretty big fan of the 3DS Zelda remakes' gyro aiming. Splatoon is a natural extension of that. So I feel like once I get used to the gyro controls I'm going to be quite satisfied with it.