On the wii I hated the motion controls, they just didn't respond well to me and I got massively frustrated with it (nearly broke me in the first Ghirahim fight, but lucked out in the end and got a bit further in the game before I quit playing it). On the Switch I played the majority of the game with the motion controls, in fact it wasn't until that aerial combat preparation sequence that I partially switched to button controls. After that I swapped back and forth between them depending on their strength/weaknesses. Some minigames was done with button controls, but I did most of the combat with motion controls (except Demise, but that was mainly because my arm was so tired after that last Ghirahim section).
So the Switch version's motion controls are excellent and I will say due to the fluidity of the camera with them I prefer them to the button-controls (but the button-controls definitely work well, though the stick-movement to control the sword takes some getting used to - although that makes it very quick and presise). I have silicon grip covers for my joy-cons, so that definitely helps with making them fit comfortably in my hands (and also makes handheld gaming a joy).