I don't remember there being a lot of substantial rumors. Monstropolis was definitely one but I never gave much weight to it. Up until Mission Breakout's announcement, the majority of rumors never seemed to materialize (which is why I doubted MB was a real thing until it was).
The official plans that were revealed mostly were just aesthetic changes to the land, most notably with the Hyperion and the Animation Academy. Besides these two pieces of concept art, there was also a model revealed of the planned new façade for the Hyperion. But for the most part it was just replacing signage, new paint, and the likes that Pacific Wharf, Condor Flats, and Grizzly Peak all received - definitely nothing as major as Paradise Pier's makeover. Even though these plans wouldn't have solved all of Hollywood Land's problems, they certainly would have done a lot to help it.
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While looking for these pieces of concept art, I found old construction photos from DCA's remodel. Really made me nostalgic. I joined Disney forums back in ~2011 to follow construction updates.