Mixed feelings
Guaranteed, this will lead to mid-majors becoming less and less competitive. Amazing sophomore/junior mid-major players will transfer to Big 6 teams and 5-star busts will transfer to other Big 6 teams. I really don't see mediocre players on Big 6 teams dropping down to mid-majors but rather transferring horizontally.
This is great for Big 6 teams and even better for elite schools who need a certain role (like a PG for Duke last year). Not great for mid-majors and hence David vs Goliath. Tournament upsets will become more infrequent and the S16 will be filled with Big 6 teams (moreso than they are now).
Also, you cannot put restrictions and regulations against college player recruiting. Coach K can easily whisper in an elite opponent's ear, "I would love to see you in Duke blue next year" during the handshake. I mean, there are countless ways in which teams can recruit these players under the radar.
This is a great idea on the surface, but it will easily turn into a madhouse.
Criticism may not be agreeable, but it is necessary. It fulfils the same function as pain in the human body. It calls attention to an unhealthy state of things. - Winston Churchill
President of the "Nolan Smith Should Have His Jersey in The Rafters" Club