It's a great trend, I think. Players are ordinary workers/asset owners and not slaves, so it is fair that they manage their labor, and not some “third parties”. It is clear that in the future we will still see cases where one club receives huge amounts of money simply for the fact that it breaks a contract with a player early, but in most cases, the beneficiaries will be the players themselves.
I don't see anything wrong with a club taking huge money for the sale of a player. They have a contract with that player and if the player wants to leave the club that wants him has to pay the asking price. If the player stays and sees out his contract then that's a win-win for both the player, and the clubs.
I also like the idea of a "release clause". This helps the player gain some money from the sale too. Why I like it because since the player has a contract with a club if another club wants him, you have to trigger his release clause.
Also, if the transfer of the player was not up to the club but to the player alone, the player can just negotiate with another club and agree to sign for them thereby disrupting the plans of his current club.
I never said that any party (player or club) can terminate a contract without paying compensation. I compare the current situation with the past, when clubs “traded” their rights to players but paying a signing bonus was not accepted (at least in modern amounts). Now the situation has changed and in fact there is no difference whether you buy a player with a valid contract (pay compensation to another club) or a free agent (pay a signing bonus).