I think 3 ranges is better, the range indicates whether it is a good height what what you are looking for, and is still vague enough that it can't be used easily to share information. However, I think there should be varied height ranges and it shouldn't be fixed. So in your suggestion, a 7'0" player will be listed in the third range every time.
I am suggesting that if a player is 6'8" then a range should be created around the player automatically, so the range could be 6'7" - 7'3" or it could be 6'1" to 6"8". Basically the given height is used to create a small range around the height. The range will always contain the same number of heights. But there is no way to tell where in the range the height is, and it makes it impossible to share information.