Now, I'm going to skip to #3 for the moment.
Unless I'm mistaken*, under the current rules, a team can lose several players to the portal after the signing deadline and find itself in pretty desperate shape at a given position. But, since, they are not granted an extra incoming scholarship, they have no way of filling this position of need that was created by allowing a player to put himself in the portal. They can't currently even go into the portal to grab someone else.
Hence the clear need for rule change #3.
* And if I am, I am confident I will receive a snarky reply to let me know.