I think you are looking through extreme rose colored glasses to see that in TLC, but next year should show more.
You say he has gotten better as the year progresses, but the stats dont really bear that out, nor does my eye. He has played a great deal more in March, but his shooting is still awful (and consistent with his season), his PPG are up just because of minutes.
Optimistically, his best game was the last one, sadly we don't get to play Brooklyn every game.
I really dont see the "great quickness". He is quick, but to me seems surprisingly not as quick as one would expect given his lack of size. He certainly isnt blowing buy guys with he ball, this month he is averaging almost 25 minutes a game but only 4.1 2 pt shots per game, and many of them are jump shots.
I hope your optimism is correct. Lets see what he looks like coming back next season, but to me he basically has shown nothing this year except defense.
He does have a very funny statistically oddity, his career high for steals is 1. He has gotten it in 20 games, infact he average 0.7 steals / game this month, but he has never had a 2 steal game, even in the preseason. Weird.