IMO the only issue with this is when a player declares for the draft, the college then gives his scholarship to another player, and then the kid doesn't get drafted. Or in your mind would the school be required to hold his roster spot until after the draft? I just think you have to make a decision and stick with it and there needs to be a cutoff before the draft. Again, just my opinion. If a HS player wants to go in the draft and doesn't get drafted, then I think his options should be try and sign as an undrafted FA and go to the D/G League, or go to JUCO. Because you don't want situations where either a) a school such as Duke gave the roster spot to someone else and now the kid has nowhere to go or b) a school such as Duke invests years recruiting a kid, he commits, Duke stops going after similar recruits because they locked up the player they wanted, those other recruits commit to other schools, and then if Duke's kid then decides to enter the draft, now Duke no longer has that kid, and no chance of replacing him with other similar talent because they committed elsewhere.
I just think there's opportunities here for both the recruits and the schools to get screwed over in the process. I do like the baseball rule where if you go to a 4 year school you have to stay at least 3 years OR you can try and go directly out of HS. But I think there needs to be some tweaks as to the deadline for when a HS player declares for the draft, and once he commits to the draft, I still don't know the best possible solution for if he doesn't get drafted. But to me, letting him go back to the college team he signed with if he doesn't get drafted can just have a lot of consequences that people don't see. Like for example, Duke gets a player to commit, he enters draft, Duke gives his roster spot away, kid doesn't get drafted, now can't go to Duke, so if he chooses another 4 year school, now he's "stuck" there for 3 years (obviously he can transfer, but he can't leave after a year to try pro ball again). I think you'd see more undrafted HS players going overseas, D/G League, or JUCO.
Again, just my two cents.