I completely agree. Either a maximum of players or introducing a NBA like system (what is it called? "luxury tax or something no? well in any case the system that the New York Knicks are very familiar with :-)
Otherwise it will become amazingly difficult for new managers to recruit anyone, as prices will go up and up
PS: agents fee might be the solution, but I am not sure though how it will be calculated (standard fee, depending on the player's salary? depending also on date pf purchase and resale?)