Im curious as to what all the A rank players are using.
Personally I can't stand how imprecise the stick controls are...they just feel wrong, like the people making this game didn't know how to make good stick controls. I can't quite place whats so off about them...
I had that same feeling, so I stopped using the stick controls, but the other day I went back and tried them out to figure exactly what it was about them that threw me off. I just now went and played Battlefield Hardline to compare the controls. The problem I ran into is how the sensitivity on the stick works in Splatoon. The range of speeds you can turn at from lightly tapping the stick to holding it all the way down is much smaller than in a game like Battlefield. Basically, when you lightly tap the stick you're turning at a speed that's much closer to the max speed than it should be. This makes refined aim practically impossible on any sensitivity but the lowest, in my opinion. And as a result, on the lowest sensitivity you lose the ability to turn around quickly.
Another problem is that the upward and sideways turning speeds are the same. In Battlefield Hardline, your vertical sensitivity is lower than sideways sensitivity, which just means that you turn around faster than you look up and down. That works well in a shooter, because the player is turning all the way around frequently, but only ever looks a moderate distance beneath and above the center of the screen. Think of how often you look straight up or down, and also the fact that you cannot continuously turn up to face behind you (wouldn't that be something). The motion controls kind of capture that perfectly, you're only going to tilt the gamepad so far upward or downward, so the gyro controls can cover that aspect, but you have to turn all the way around, so the stick lets you do that.
Man that was a lot longer than I thought it would be. TL;DR: The stick sensitivity in Splatoon is unrefined which makes minor adjustments to your aim impossible on higher sensitivities, and makes turning around a pain on the lower ones. I'm not saying that stick controls in general are bad, just that the ones in Splatoon could use some work.