I care very little for anything being removed, but they will need new shows to replace their capacity. And I'm sure this will happen. Most people care most about rides and they take longer to design and build, so we hear about them first. We already know of two new shows in the works for big theaters and the increase in capacity (and move indoors) for Jedi Training. Animation gets repurposed. My belief is that the following would be a conservative expectation list (and hopefully what we get is better than this):
Lose Indy but get new LPS E ticket with high capacity (Indy sees 10000/day; an appropriate ride should do better)
Star Tours converts to second E (still not convinced, but we are being conservative)--no net capacity shift
Empty Sounds Dangerous to Jedi Training Academy; capacity increase
Frozen stays
Animation repurposed, stays a pavilion. No net change
Keep Disney Junior
BatB converts to villain show and gets enclosed. No net change
New daytime show in Hollywood Hills. Extra 5000 people entertained at least 3x per day
Lose Mermaid (pretty big capacity drop, about 600 per hour), OMD and Sparrow (more modest loss)
Increase TSMM capacity by about 500 guests per hour
Slink Dog Coaster 1500 per hour
Alien ride 600 per hour if it is Mater clone as I think
Extra 2600 guests per hour for Toy Story Land more than replace capacity lost from Mermaid, OMD, and Sparrow. Should be an increase for Star Wars if we indeed lose Indy and Star Tours is just repurposed, and of course there is the benefit in both cases of replacing old with new. New Fantasmic show increases capacity further if we get that.
What we can't really account for is Backlot Tour (2400/hour although it wasn't popular enough to achieve that) and LMA (3000/day)/Muppets (600/hour) if they are removed. Toy Story Land takes up a little of BLT's land, so it should cover some of that capacity (which it can easily do in addition to covering for Mermaid, OMD, and Sparrow). The modest Star Wars project discussed here wouldn't require any of those, so it's a different project that would require their full removal. Based upon what we have so far, though, there an increase in absolute capacity for the modest Star Wars land or Toy Story Land and an even greater increase due to replacing some unpopular attractions. We will have to wait to see what, if anything, is announced for the back of the park.
