My ideal electoral reform

[Angel of Death]

Elect the president, senators and the sole representatives of a state using approval voting.
Other representatives are elected through proportional representation, either, if the state has many representatives, using open party-list proportional representation using Webster/Sainte-Laguë (where "open" means that the number of preferential votes are paramount in determining candidate election) or, if the state has few representatives, using Single Transferable Vote using Droop Quota.

Of course, because this would effectively destroy the two-party system and the accompanied corporate political clout, it will never happen.