To me the first question to be asked is how/why minor league professional sports should be tied to institutions of higher education. As ineffective as the NCAA is, there was a time not to long ago when APR and progress towards degree rules, among others, at least provided the semblance of "student/athletes" existing on college campuses. That is no longer the case. Therefore, I ask again, how/why should minor league professional sports be tied to institutions of higher education.
The proposals by the OP all make sense and would help but nothing in them address the educational mission of the institution. And it's fine and good to talk about those who otherwise would not pursue higher education being able to do so via athletics, but we are talking about a relative small population (mostly men's football and basketball players and perhaps women's basketball) as most of those in non-rev sports are students who play sports. But is educating such a small group worth what universities put themselves through to have this giant appendage that sucks all the air out of the room?
Let me dispel another myth - most studies I have seen find no or a very small relationship between athletic success and non-athletic giving to the university.
If these truly are student/athletes, why do they deserve to be paid? Or better, why do they deserve to be paid more than a physics student who works in a lab is paid? Yes, the athletic department makes millions and perhaps players deserve to share in that, but isn't that called "professional sports?" If so, I ask again, how/why should minor league professional sports be tied to a university.
The best solution I have ever heard was by former Chicago sportswriter Rick Telander in his 1989 book "The 100 Yard Lie." Among other proposals, Telander suggests college sports be run more or less like they are (i.e., athletes would be recruited from HS, they would have five years of eligibility, etc). However, when they are playing, they have no academic requirements to fulfill. They are simply athletes. But for each year of sports participation they receive one full years of tuition, room/board, books, etc. Some, like Derrick Henry, may never use that. Others, like a second string tackle who doesn't get drafted, might play four years then complete their college degree. Some might play a couple of years, realize life is passing them by, and take their two years of education and pay for two and move on.
But this would solve the issue no one wants to talk about, that being the fact that these are not student/athletes, but rather are minor league professional athletes who are being stuck in a university.
One last thing. Among the P4 conferences almost all the athletic programs, if not all, are self-supporting (i.e., they take no money from the university). Once you get below that level, that is not the case. There you have universities using student fees to prop up athletics, mostly football.
An anecdote. When I was an UG at Kentucky, a long time ago to be sure, every student had to pay a $25 "athletic fee." That was justified by us getting free tickets. However, on a campus with around 23,000 students and another 15,000 or so in the community college system as you might guess, not every student could get a ticket. A friend ran for SGA President and one of his platform planks was doing away with that. He was called into the President's office where he met with the President, AD, and a few others and was while I won't say he was threatened, he was threatened.
Following COVID when athletic programs were shutting down sports, I did a little digging and found the athletic budge for Bowling Green State University. The second biggest revenue source for the athletic department was student fees that, at that time, were close to $700/semester. And people scream about the cost of higher education when every student is being asked to pony up for a mediocre football team so a few fat cat alums can be happy.