Sorry if it's a bit offtopic and i'm risking sounding like an armchair imagineer here, but i'll repost an image I made showing seemingly unused land that could possibly be used for expansion at MK.
I'm not sure if every plot of land I marked can be realistically used (perhaps with enough money and ambition any of it). But look specifically at the land marked to the east of the Circus area (outside the train track), which was actually an officially designated expansion plot for future use when the park was first built. One assumes a pathway either underneath or over the track would connect the area. Assuming they could fill in and reroute the water to use the entire area, there's enough space to almost double the size of Fantasyland if so desired (it's a bit bigger than all of New Fantasyland including the Circus area). Lots of room for a Frozen miniland with plenty of space left over.