For example, my local conservative candidate has done a really good job over the years and done a lot for area, resulting in him having a huge majority for a long time and for me voting for him again.

However, as a national leader / potential prime minister, I hate Cameron with an unexplicable vengence and don't want to see him in charge.

Therefore, why don't we have 2 votes, one who you want to win locally and another for nationally, so, in this circumstance of a hung parliament they can turn to vote no. 2?

You seem to be advocating a top up vote system like the one we have for the Scottish Parliament. You vote for your local MSP (or MP) in the usual way, and then vote for a party on the second sheet.

Candidates selected based on the second vote don't represent a constituency, but represent an area formed by a group of constituencies (so no-one really).

Downside of this is that a chunk of your elected individuals do not answer directly to a constituency. It will amost invariably lead to a coalition government too, which, depending on your point of view, is a good or a bad thing.

You do

Are you telling me you're no a member of the Tory party?

😉

Crickey, we're having enough trouble with just one vote each
😉

CC