in other words you mean to manipulate the price!
not only you want to do an illegal fund-raising called ICO but also you want to do another illegal thing called manipulating the price. because that is what putting up a buy wall to prevent crash of the market means.

instead of coming up with ways to protect the price with tooth and nail, you should think of ways to protect the price with real development. create something that is really useful like bitcoin, and the price of it will go up on its own with the real demand it gains.