I'm not the one you asked, but my solution is to encourage further the developments that are already taking place. The U.S. House of Representatives has condemned SCOTUS's reasoning, and moves are afoot in Virginia, Oklahoma, and Missouri to restrain the use of eminent domain. If we can apply political energy towards making our state legislatures pass unequivocal resolutions indicating that use of eminent domain for private development is unconstitutional, it would be far more likely to see results than an attempt at formally amending the U.S. Constitution.
Also, a statutory prohibition of federal funding toward any project in which property seized by eminent domain is transferred to (other) private hands would go a long way.