A college would not penalize an actor who was fortunate enough to gain an Equity card. He can still try out for the school play. A student trumpeter good enough to join the Musician's Union can still play in the school band - in fact, he likely gets the solo. And so on for all the other activities in which students can engage. Athletes should be no different, with a couple of modest exceptions.
(1) The reform suggestion is thus elegant in its simplicity. Reduce the essential enforcement obligation to the school mode - academic eligibility and a strict ban on illicit benefits from the school itself (level playing field). After that, anything is fair.
(2) Getting to details, first, begin with a whole class of exempt entities - the NFL, MLB, NBA, soccer leagues, reputable enrolled agents (certification program), and so on. These and their executives are exempt from enforcement - by definition, they're not college affiliates.
Second, define 'booster' as broiadly as you like - faculty, alums, season ticket holders, donors above a certain amount, relatives of team members - throw in your own additions. No financial arrangements with this group is permitted.
The athlete would be required to report any deal that is not with an exempt to the athletic department, where it escrows for a 30 or 60 day perios - long enough for the AD to verify that the deal is NOT with a booster. If not, then it goes forward.
And that's it. I'm sure some readers will come forward with science fiction thoughts about the Cayman Islands, nominee accounts, and the like. But since it's not happening now, it wouldn't happen then.
Finally, though I wish complete consistency was possible, a schedule for autpgraph signings and memorabilia sales would probably be necessary. But that's easy.
(3) Most important, practically, I would expect that most athletes with real career potential would arrive on campus with some affiliation already in hand. I'm discussing the NCAA here, not the NBA or the others - but I would envision a draft of all free agents every year, and a basic format of 4 year option contracts, scheduled along the present lottery lines.
(Thus, an Andrew Wiggin would be drafted first - if the club thought he was good enough to play right then, he immediately joins the franchise. But few are. So he pockets one-quarter of the first round money, and enrolls at Kansas. When and if the parent club believes he can play, it exercises the option, and he joins the club. The franchise credits the option money it has already paid against the first year salary due. Some of my readers wrongly see this as converting to the club mode, so the athlete can be 'called up' at any time. But I don't see that happening - I think it's a pretty easy negotiation for NCAA, NBA, and the coaching fraternity to work out. We stay in school mode - the option is exercised at the end of the season, probably with more notice than coaches get now.
The point is that an athlete in Wiggin's position has no interest in taking the comparative nickels and dimes that boosters add, and endager the exposure on which the really big money depends. For their part, boosters have not much interest in crippling the school, and not too much in spomnsoring third string point guards. Giving legitimate access to pro money and support actually makes enforcement far easier).
The result would be a system in which athletes, like every other student, explore all the life options open to them; colleges get the benefit of the revenues generated from the system they created; the athletes fairly exploit the financial potential of their ability with the larger world; and the fairness of the system is incredibly enhanced. Players who are good enough to join a professional franchise probably should. Players who are still developing their potential can develop ALL their potential as human beings, not simply as athletes.
Drastically simplifying the system by reducing enforcement to what school sports are all about works for just about everyone in the system. Time to put the phantom menance of boosterism behind, and think hard about how college and professional sports actually interrelate in the 21st Century.