There's no particular reason why we have to change to an ACTIVE president. We could just have a figurehead, in the same way that Brenda is one at the moment. But we'd get rid of the residual powers, which aren't used but theoretically could be- Constantine of Greece pulled that trick with the military coup back in 1967. Ireland seems to get by well enough with some ex popstar or time-expired politician. Elect them for say 10 years, even Royals could stand. And a simple ballot system with write-ins could be fun.