My random thoughts:
The gyro controls are great, I practiced with metroid blast for a couple weeks on and off before hand so by the time I was in the game it just felt natural to me. I used the splattershot and won every single match I played in and ranked first with the most kills in 90% of them. I rotated lobbies about 4 times.
Swimming through the ink feels great. Whenever I encountered an enemy I would immediately dive into the ink and flank them, using the right analog to keep them somewhat centered then popping up and using gyro to fine tune my aim and KO them.
I like how you can aim while you're still in the air when super jumping to your teammates. It's a great way to get a good survey of the map and plan out your route.
Normal jumping didn't feel great to me, it was slow and low in both squid and inkling form.
Couldn't really get much going with the splat charger, didn't cover a lot of ink and was hard to KO with it.
It's a shame everyone is saying the gyro controls are shit and to turn them off, when they're obviously just not used to them. In my opinion they offer a far superior aiming experience to dual analog and even wiimote. I found myself using the gyros ~80% of the time.
One thing I need to master is quick 180 degree turns by moving backwards and hitting Y to recenter the camera. Died a couple times to people I knew were behind me but couldn't quite react quick enough.