These issues all depend on a number of different factors. How many fouls and free throws per game are you and the CPU getting? How much of the shot clock are you and the CPU using up per possession? Which type of shots are you/the CPU missing too many of (wide open shots, mid range, three point, low post, contested shots, etc).
The more info I have, the more I can help you out.
Yes, this was a necessary evil to increase the amount of realistic blocks. For some reason, 2k seems to have gotten the Vertical attribute to work perfectly with the Rebounding attributes, but it seems to have very little effect on the players' blocking ability.
Have you ever noticed how, when you go up for a block, your player seems to barely leave the ground? But on rebounds, the players get realistic height when they jump? In order to make blocks more realistic, Vertical had to be raised. Fortunately the negative effects of raising the Vertical attribute are almost entirely aesthetic and not functional in nature.
I'm looking to decrease Vertical slightly while maintaining the improvements to in-game blocking, so hopefully this minor inconvenience is solved soon.