...Japan really looks like only 1 attraction. No way Hollywood would get something additional when our space is even smaller.
Things look different from what they appear to be, after-all.
Let's assume for a moment that in Japan, the parking lot to the right of the Mario Kart building is used for future expansion and the park opens with the Mushroom Kingdom and Mario Kart attractions. The overall size between USH and USJ isn't really that big. 0.2 of an acre. Here's what USJ's layout looks like overlaid onto of USH (for a more accurate representation). By rotating the MK building Hollywood was able to gain valuable space. This would leave SS 18, 19 and 20 perfect for expansion similar to USJ's parking lot.
View attachment 9005
I get the feeling, once aerial's get updated on satellites, things may become a bit clearer.