As it's a federal election, Congress could also preempt this by imposing commissions nationwide through the normal legislative process. This strikes me as highly likely if Democrats control the federal government in 2021.
What about state legislative districts being gerrymandered? I don't think Congress could do anything about that. But I have another suggestion: adopt a constitutional amendment that requires all of the states to use independent redistricting commissions for both congressional districts and state legislative districts. In my signature I talk about rewriting the 14th Amendment to make its meaning narrower and clearer. I have drafted exactly how I think the rewrite should read, and I included a provision for redistricting commissions. Here is how my proposal is currently worded: "States shall adopt redistricting processes to assure that congressional, state, and local legislative districts will not be 'gerrymandered.' Iowa’s Legislative Services Bureau is one example of a permissible redistricting process, or states may adopt independent redistricting commissions; using algorithms is encouraged, but the power to draw districts must be taken away from each state legislature."
My proposal, more broadly, deals with the vague language in the second sentence of Section 1 of the 14th Amendment. I drafted a rewrite to make the rules that states have to obey more precise, clearer, and narrower. In my draft, I enumerate which "rights" the states cannot violate, and I make clear that the Ninth Amendment is only binding on the federal government, not the states. And I enumerate the kinds of discrimination that states cannot engage in. I continue to protect the equal right of all citizens to vote according to all precedents (except for
Bush v. Gore decided thus far.
In order to get over the hurdle of our current nation's polarization and intense partisanship, I decided to include elements in the proposal that will appeal to both sides. That is, some elements will be appealing to conservatives but repulsive to liberals, while other elements will have the opposite effect. Therefore there are things in it for both sides to root for, and both sides can accept it as a compromise.