I think it's a shame the voting referendum in 2011 didn't change anything. First Past The Post is such a frustrating system because if you're in a marginal constituency you often have to vote for the lesser of two evils, or if you're in a firm Labour/Conservative seat then voting for the party you believe in may not have any effect. I can see why people don't vote (although I think everyone needs to vote - we need to make our voices heard in whatever ways we can, however much/little of a difference people think it makes).
People didn't really turn up to the voting referendum and it's a shame because I think AV or STV would be a really good idea - it gets rid of the "tactical voting" element to an extent, although there are some issues that need to be worked out with it. Apparently it can lead to bigger landslides in landslide votes but I don't know enough about the complexities of the voting system to say whether that's enough of an issue to make it worth dismissing as a system.
In any case though, the Tories did get the majority of the votes - even if it was 36% compared to 30%, it is still a majority - but should that be enough for them to have over half the seats?