This game is a patch away from being really great, and I am already throughly enjoying it on the Switch.
I have had no problem with shooting, reliably hitting dunks, 3's and close shots with two Epic players. I agree that it's annoying that they aren't clearer about ideal release range for different shot types, but I think it's pretty easy to figure out once you start playing.
The things I have struggled with are rebounds, shot blocking and loose ball retrieval,but some of that is to be expected this early on with the game. All the reports of "steal spamming" breaking the game are oversold, if anything it's crossover heavy CPU's that are impossible to stop.
Game looks fine to me in portable mode, but I am also not a resolution stickler. I honestly forgot about that gripe completely until about an hour in.
Overall, there are some balance issues, optimizing and game modes that need to be addressed/added but this game is super fun already. It's also really refreshing to play a game with packs that isn't dependent on virtual currency and micro transactions.