If the court rules that individual states can not determine eligibility the door would be open to all third parties for ballot access challenges. The court would have to set up or help to establish federal rules to determine eligibility requirements or face a flood of challenges for all 50 states. That seems to be a nail in the coffin of Federalism. A Trump victory in SCOTUS would set up a 50 state rush of indie candidates who would take eligibility questions to the high court. To avoid that they would have to legislate from the bench or convince Congress to legislate an end to Federalism!
Balanced nutrition for the nation's minds!