I 100% believe that the new attraction in place of Stage 28 will be an "after Potter" project, and for now they'll just get started with the plans, demolition, and maybe even construction, but not have it open until after Potter.
As for how they made the Lower Lot all nice in 2012, it was just cosmetic. This "last minute" development of taking control of Stage 28 for the theme park expansion definitely shows to me that it wasn't originally in the plan, and Universal can go back and redo most of the lower lot around Transformers again.
As for viewing angles for the facade/mural, hopefully this new development will have Universal rethink the design of the facade once again.