I have to say that as a long-time bring-back-dreamfinder kinda guy that a Phineas & Ferb version of the Imagination pavilion would be awesome! Especially if they turn the old ImageWorks into a climax for the Agent P stuff like the temporarily did for the Kim Possible stuff.
This Since I watch P&F with my kids I would be equally as interested in seeing that happen! You wouldn't be able to step foot in that building We did the P&F at Epcot and it was fairly busy for late August.