This partneship system really gets me excited, for example TNA's wrestlers working on NJPW and AAA.
But, to answer your question:
I would also change the overnesss system. I mean, Kevin Steen in one of the most over wrestlers on the Indy Scene, but if he eventually goes to WWE, he is gonna be a nobody and almost no one will chant his name and etc. And this happens on the indy scene itself too. Brandon Gatson is very over at PWG and west coast feds, but if he works a show for ROH on the NY he is not gonna be over with the local crowd.
I propose you to put different levels of overness for diferent promotions according to their time wrestling for which pomotion, and if I book a feud where a wrestlers gets over, he is going to be over only in my fed. You know what I mean?
Sorry for my english, Im from a non-english language country. Thanks!