An incredibles ride could be absolutely incredible, if done correctly. I think that they could either go with a ride system like spiderman in IoA or like the original Harry potter ride with the VUVA arm (I think that's what it's called). Maybe an Incredibles ride like spiderman and a Monsters Inc door ride with the Vuva arm? Not trying to recreate Uni rides at HS but I also think that the ride system used in escape from gringotts could work beautifully in Star Wars ride, especially the one with the fight between the First Order and Resistance.
As for the whole Pixar Land vs. TSL, I think Pixar Land (my preference) would be great in that it would have a rich library of characters to make a ton of great rides, but the land would look a bit fragmented, considering the different places Pixar movies take place in. On the other hand, TSL is (seemingly) a bit lacking on exciting new rides, but the scenery should be amazing. TSL is also a good thing for the younger kids who really have very little to do in HS compared to the other parks.
For the empty space, I would not like to see Cars Land, ESPECIALLY if it would be a smaller/dumbed-down version of the one at Dca. I would rather see Pixar rides such as the aforementioned Monsters Inc and Incredibles rides in the area where LCA and SoA are now. I think (in a while after SWL, TSL, and whatever is in the LCA/SoA area) a villains section would be PHENOMENAL. Maybe they could expand behind RnRc or around where the animation building is (don't know if there's ample space). I would love to see a dark ride there,and maybe a thrilling coaster, kind of like EE