They should make any games not covered by your RSN but shown on the opponents RSN have the blackout lifted.
I also hate even with MLB EI you cannot view the opposing teams feed. When the Yankees play the Orioles this week even if I had EI I could not watch the YES feed of the game. All non Orioles games you can watch the Yankees feed on EI. They should but they never will should give the opposing teams feeds as well with a subscription to EI.
Why should the other feed be opened up? The RSNs pay a ton of money for exclusivity.