Right now the limitation of 4 overseas players is only benefiting these oldies and not any younger player. Also, there are plans to increase the number of teams from the current 8 to either 9 or 10, and that should give room for fringe players.
There are some young talents that were in display and if not for the IPL we would not hear from them and there was one player from MI who was consistent throughout the tournament and did not get a place in the Australian tour and there was legit heat from everyone for not including that player, if not for the IPL no one would know about him or his performance, it is helping the young players as well as the retired players 
.Obviously with the domestic cricket in India not being in good shape, the IPL is the primary platform for the younger players to showcase their talent in front of the selectors. A number of good young players were noticed during this edition of the IPL. My only concern is that the test format may get overshadowed by the glitz of IPL. Everyone is after T20 these days.