There’s a constitutional problem - a clause saying that no state may be deprived of its its equal vote in the Senate without its permission. Given that the Constitution enshrines the electoral college for choosing Presidents, any federal or state laws affecting that seem unconstitutional given the equal vote in the Senate requirement.
The biggest red flag on Democrat agendas re: all of this and more is the proposal to expand and pack the Supreme Court and/or issue term limits for Justices.