I understand your concern.

Lowering of the ratings is because they are too high to begin with.

Agility is how fast you perform moves, lateral movement, and transition into into dunks). Lowering this makes them move in a more fluid motion, more grounded motion (less ice skating feeling)

Vertical, self explanatory, players jump a little too high out the box (this has been an issue for years).

Standing dunk (only big men should be able to pull this off and some high fliers) but when I saw Leonardo Barbosa and Ron Artest pull off a standing dunk, I knew this had to be modified.

Believe me, the game plays smoother with those global edits changed. The developers did many good things with the game, we aren't taking anything away from them, rather we are enhancing with sliders an enhanced experience. The Live team many times follow these forums and implement them into their plans and patches, thats why its important for the community to get involved.