Older means more prone to injuries and fatigue. Baron Davis is not even as old as Kidd and Camby, but you can see his age while he was playing.
The youngest players are Lin, Shump, now that they got rid of Jorts and JJ, and Shump is out for a big part of the season.
If Nets get D12, it's over. Not too old, not too young players, just right.