There's a distinction between the complexity of choosing how to vote, completing a ballot paper and administering an election. I don't expect any one can be minimised without raising another.
The tradeoff might be made easier by expecting less of any single elected body/office. If we had a national legislating chamber, elected by at-large proportional representation from a single constituency, and we turned instead to local government for geographic representation, and the second legislative chamber were elected by local government to exert geographic influence over legislation, then maybe voters could make fewer, easier, and more impactful choices. I don't know of any country that works like this, but Germany is close.
The tradeoff might be made easier by expecting less of any single elected body/office. If we had a national legislating chamber, elected by at-large proportional representation from a single constituency, and we turned instead to local government for geographic representation, and the second legislative chamber were elected by local government to exert geographic influence over legislation, then maybe voters could make fewer, easier, and more impactful choices. I don't know of any country that works like this, but Germany is close.