With the direction WDW management and the company overall has been going, it's doubtful that we'll see an original attraction that isn't related to the latest Pixar franchise. That said, they could easily add the Ratatouille ride being developed for WDS Paris to Epcot's France pavilion instead of the previously rumored location in the Pixar Studio section of DHS. Its a closer thematic fit in the France pavilion, and Epcot sorely needs more attractions for children. The ride doesn't seem to have a very large footprint, and it looks like there's more than enough room behind France:
(also: who knew the mini Eiffel Tower was actually perched atop the back of the Impressions de France building?)
edit: here's a look from other angles
They could even replace the old Impressions de France CircleVision film, which opened in with the park in '82, with the Ratatouille ride. I don't think it'll be much of a loss.
Disney...are you listening?