Speed, Strength. These are things that at this point, are equal on all players it seems. I don't know about you guys, but I tend to find 5'11 people just a "wee" bit quicker than most 7' people. Likewise, I can't say I ever remember Mugsy Bogues ripping a rebound out of Patrick Ewings hands.
Speed can affect defense, driving, how often a player gets fouled, handling.
Strength effect rebounding, shot blocking, inside shot/defense
On top of that, what about some tactics like half-court traps, or 1-2-1-1 zones?