I got the game yesterday for PS4 and have been playing a bit online... Brief thoughts:
1) Thunder are really easy to play with on defense. Russ, Oladipo, Roberson, Payne, and Morrow are all really good at getting steals, which is something that is now important in the new meta-game. Moreover, Adams covers for aggressive defensive mistakes.
2) Guys like Kyrie, Westbrook, and Wall can penetrate just as easy off of screens as they can in real life. I thought this was a HUGE improvement compared to other games.
3) LeBron is too slow and poor at driving.
4) I really like the new playbooks. Much more realistic.