We are not EA... So we can't edit anything in-game.
The sunsphere is an aspirational building, all aspirational buildings are expensive.
Also, The Sunsphere is actually the cheapest out of all of them too! :)
No reason to save up for the sunsphere untill you are level 38 and have everything. The aspirational buildings were made for the people who have finished everything and have nothing to spend their extra cash on. Things also in the same category as the The Sunsphere are the Escalator To Nowhere,Popsicle Stick Skyscraper, 50ft Magnifying Glass, and the World's Largest Zirconia. (Or at least the ones that are still available)