To me it feels that it is more demanding than it should be in general. Even docked, my Switch lights on fire. About battery life, I have found it to last about 3.5 to 4 hours with flight mode enabled.
Yeah it feels like there are some optimization issues since I get stutters fromme time to time.
I’ve never played my battery flat, but I go to about 40% in 1,5 hours in flight mode at about 20 % screen brightness. Compared to Splatoon it’s a faster battery drain (one should also consider that with Splatoon Wi-fi is on).
EDIT:// the stutters does not hurt the game at all tho, after all it’s a turn based game.