HS baseball players are allowed to have agents negotiate for/with them and not have their eligibility at risk should they decide to go to college instead of playing pro ball. Not sure how it works with hockey, but must be similar. I'd assume the relationship stays intact even if they go to college and the agents are still in communication with the pro teams.
My thing with college sports is, one rule for all sports. It's silly to have different rules for how the business side of things operate.
Football: Must be 3 years out of HS?! No dealing with agents
Baseball: I think they have two windows to declare. Can have agents during HS.
Baseketball: Must be 1 year out of HS or graduating class? No dealing with agents.
That's the problem with the NCAA. Different standards...and that includes the member schools that make up the NCAA (looking at you UNC...ahem...)
The NCAA does not have a rule that forces "NBA ready" kids into one and done. That is a result of the CBA the players and owners in the NBA signed. It lasts until 2023 IIRC. MBL and the NHL have their own agreement with the players, as do the NFL owners.
The NCAA could do any one of several things, but are unlikely to do anything. I agree with those who say the freshman eligibility rule isn't likely to change, but it would work. Another thing I would like to see discussed is for the NCAA to change the LOI process so that players signed a binding contract with the college. That could be structured to keep them "employed" for five years, or their graduation, and prevents them from playing anywhere else for compensation until the terms of the contract are satisfied. If a player wants to play professionally, he would have to skip college or wait until graduation. That is essentially what baseball and hockey players are doing now. The difference being this rule rule would guarantee the players five years of college.
The sneaky part of this option is the players would be getting compensation rather than a grant, so it would be taxable. I think the NCAA could give the colleges room to negotiate with players for additional money, up to a point, without tilting the balance too far toward the wealthiest programs. There would certainly be a transition period and bumps along the way. But that would acknowledge that the players are getting paid, but make sure all the players are, in fact, students. What it would not do is protect against a UNC style cheating scheme.