The main problem with this system: even most university educated people cannot thoroughly understand it. [0] That potentially undermines trust in the system.
As a bit on an anecdote, I know two Canadians, and I asked them if they were voting in the upcoming election. They both answered 'Maybe, but there is really no point, since liberals/conservatives always wins my riding anyway', and that made me pretty sad. I wonder how many people live in Democracies where their vote just don't matter at all?
The best would be a simple, proportional and geographically representative system. But if we can't have all, I think dropping simple is better.
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.