Okay...piecing this together from what's been said in this thread, some morsels from across the intertubes, and my Marvel fanboyism going into overdrive, here's what I think...
*WARNING* WILD INTERNET SPECULATION APPROACHING *WARNING*
Okay, so starting from the front of MSHI, we have the Hulk and Stormforce Acceleration to our left. If the land is moving into MCU territory as expected, the X-Men are not a part of that Universe. On top of that, Marvel Studios and Fox are in a blood war. There's no love lost between the two, and it's quite honestly a very petty feud. Marvel has been doing its best to handcuff Fox by doing everything from cancelling comics like Fantastic Four to not allowing new X-Men to appear in the comics. Due to this, I could see them requesting StormForce be given a new theme. With Hulk seemingly also on the table for a retheming, why not tie that area together. Hulk and Storm become the SHIELD or Avengers Training Grounds. Both rides become proving grounds for guests to prove they have what it takes to become a superhero or a SHIELD agent. Throw in some SHIELD theming and preshows from Agent Coulson and Nick Fury, and you've got yourself a new theme.
Moving on, and continuing with the theme of erasing the Fox properties from the park, Café 4 becomes the SHIELD mess hall.
Next we have Doctor Doom's Fearfall. My guess is it gets ripped out and replaced with a brand new Avengers E-ticket.
From there the land just receives some major theming enhancements to bring it to the "real" look of the Marvel Cinematic Universe. God willing it also ends up giving us something cool in the Toon lagoon theater section, but I'm not holding my breath for that.
Again, this is NOT insider info. This is just me spitballing ideas from the random crap in this thread that I think could make sense.
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Neither Hulk nor Spider-man will be replaced, if I was a betting man.