Before i begin i need to address Avatar and Star Wars land. I'm sure Disney will do a great job with both of these but lets be honest the source material used is not hard scifi. that's not to say star wars is bad (so no one start jumping on me) its just both series's are really action adventure more than scifi and the lands made for them will emphasis action adventure that's not to say its a bad thing, just they wont focus on certain elements that I'll be using.with that out of the way please don't mention how my suggestions are similar to star wars and avatar land, now lets update Tomorrow land. First understand that all the content should be original and not using other source materials also technology will only be used for the stories sake not as a main highlight or focus.
The entrance will be an attraction much like star tours or mission space. the exterior will be a space ship that is not a rocket or UFO . it'll have some sort of engine that will safely fire out in front of guests. obviously they'll be other entrances just to enter Tomorrow land if guest wish. in the attraction the story is that guests find themselves in a far flung future the second or third explorers to travel to an alien planet in another solar system.(or you could create the spaceship as a sort of ark with the the last inhabitants of a dying planet traveling to a new planet becoming pioneers.) guests will experience a believable flight to the alien planet as they exit the attraction they enter this planet.
now something that will be put in the forefront of this land is to create an ALIEN environment something that guests would never suspect, something eerie and strange but also full of wonder and have a real sense of danger. heck even make the vendors of stores, restaurants, and the food itself alien. a way of doing this is probably impossible but this all theoretical anyways create a dome to cover tomorrow land and have screens on the exterior and interior of the dome. the exterior shows a launching pad of different spaceships launching or landing blending perfectly with the entrance and the interior will be an invented alien sky's, suns, moons, along with constellations of stars. also it can give forced perspective on the land itself to make it seem endless.
now the explorers would be using a machine that is slowly terraforming the planet (perhaps as a story idea used like a live mystery show you could have the machinery being sabotaged and only have a certain period of time to fix it/solve mystery before you run out of air. like having a certain part missing to reveal the culprit as the aliens of the planet. the aliens live deep underground ( which is why they weren't discovered earlier) in vast technically advance tunnels, filled with there rich history via advance sculpting in the walls of the caves. there eyesight can not stand sunlight or other forms of heat and light with the exception of certain rocks in the caves that brighten up like the northern lights. there's no explanation of why this is but scientists studying this hypothesize that a natural form of energy is in the rocks. the aliens eyes do have a form of natural night lights if you will and have higher sense of hearing. they discovered the human immigrants by the constant noises they made up above to create there base. this all eventually leads to the aliens and humans either compromising to share the planet or having a full out war leading to genocide of either species or a peace treaty being made. if you choose the peace treaty you can make it unfair and have an uneasy peace that could snap at any moment or you could just show the effects terraforming and what its doing to the planet as it was originally but please no overtly obvious preachy environmental message. also you could make the planet a dead one where aliens used to live eons ago and have archaeological digs going on discovering an ancient civilization)
other things to note, there will at least be one part of the planet as a base made by humans for human food. . other suggestion is have all the attractions, rides, and so forth show the entire history of this planet intermixed with every sub genre of science fiction/speculative fiction. also you could have an attraction on just the alien fauna and animals that live on the planet you can even created endangered or extinct species.
with all this written i just want to stress that just because this is for the family doesn't mean you shouldn't take daring risks in creating a story that has no right side, is really scary, or etc. I'll admit its a tricky to balance such things for the family but it can be done and at least should be tried.
