If the democrats retain the Senate and regain control of the house, they should repeal the reapportionment act of 1929 and you’ll mostly fix it that issue along with most of the gerrymandering issues, not to mention you won’t have to go about it trying to get a constitutional amendment that will never be ratified. The National Popular Vote Interstate Compact I don’t think survives a legal challenge, especially not in this current SCOTUS.