I'd love to see Pan and It's a Small World have their facades updated.
It'd never happen, but I'd love to see the FestHaus become IASW's queue house, the external queue demolished (widening the walkway between PP and IASW) and a proper IASW facade built that could be seen once you walk through the castle.
The enormous cement park out front (between the new IASW entrance and carousel) could get the IASW fountain like in Paris.