How would you fix the NBA declaration/withdrawal mess?

[HouWarrior]

This year, the deadline was moved up earlier on the calender, and many players declared (w/o engaging agents) to protect their options for the draft, only to see a number of them, over recent days, withdraw their names and return to school.
The NBA declaring and related NCAA eligibilty rules seem to have gotten unwieldy.
What are your thoughts for simplifications?
Baseball allows a drafted player to go to college and reenter next draft if he does not sign.
I think hockey allows similar
NFL has one stay, or permanently declare, but after 2 years of college
Should NBA allow open declarations, and NCAA allow those not drafted or drafted, but not signed, to just return to school (assuming there is no agent $ or side inducements accepted in the interim)?.
The flux it now places on some college programs almost gives them now an incentive to oversign, to hedge their bets on someone not w/drawing and returning.
There must be a better system--Ideas?