However, it is quite complex, both to the average voter who sees a strange ballot, and to the more educated voter who wishes to understand the electoral process.
It is also quite complex for the purpose of counting votes, to the point of probably requiring three or four days to do a complete count. You will also, I suspect, find a lot of resistance to the idea of "losing" candidates still making it into the legislature. That was the main tactic employed by the anti-PR forces in the Ontario referendum last year.