Keep the electoral college and the state structure but go back to #1 is Presidnet #2 Vice President.
Yes thats insane today but its the best alternative we have without destablizing the USA. If nothing else one of the two will kill the other
The Europe system and much of the worlds is inherently too unstable IMO
...Don't mess with the States system or you will get "Don't Tread on Me Flags" and if you push it well Dixieland!..lesson learned?