Here's a wacky idea: Instead of the traditional tough-parent, bad-child publisher/studio relationship, let's do like other creative industries and treat developers as adults. Let's grant them increased leeway and freedom as they earn it, instead of the constant antagonistic bond of mistrust and autocracy that turns good games bad.
Once initial surprise over the Microsoft/Bungie split evaporated, it didn't take much to recognize the universal benefits. Both firms probably see themselves as getting the long end of the stick. Microsoft keeps a property that prints money. Bungie gets its coveted independence and multiplatform options. The publisher won, the developer won. Even players won.
Bungie's reasoning behind the split was they didn't want to make nothing but Halo all their life. Halo had become a proven franchise, and the creative minds at the studio were eager to wander fresh roads. But that required a split from Microsoft, which conventional wisdom says should be unlikely, but Bungie did well for Microsoft and got something surprising - something Microsoft by no means had to give - in return.
Reapplying the core concept, imagine this: a developmental relationship between studios and publishers based on the idea of mutual back scratching, instead of a make-us-money-while-we-backseat-drive arrangement. If publishers were willing to offer the incentive of additional and escalating creative freedom as a reward for successful releases, we'd likely see much better games and much higher profits.
First Comes Broccoli, Then Comes Dessert
Time and again we see the best, most innovative games coming from self-funded studios and studios with significant creative control over their projects. Irrational, Valve and Blizzard are all good examples. Some are independent, some are not, but they each had near-total creative control over their most successful properties. They got it thanks to a consistent record of retail success. As for smaller studios lacking the autonomy of a Valve or Maxis, there's no reason why their financiers shouldn't grant them even greater leeway, provided they've earned it.
The most obvious way to implement is just as simple as a do-your-chores-before-you-watch-TV understanding: "You, studio, make my movie tie-in or expansion pack or umpteenth sequel. Manage well, come in on time and under budget and produce a successful game. I, publisher, will then reward you with unparalleled creative freedom for your next project." Work on preexisting IP may seem less onerous when developers have an incentive to get through it.