I feel you're asking the wrong question, as Political reform is needed. The problem is not the voting system, but whom we are voting for.
Introduce a law requiring:
10 years work experience outside and totally unconnected to politics, any political party, or affiliated insitutions (EG unions).
MP's salary caped at Average national wage +50%. That way if they **** the economy their wages drop, want a better pay rate, raise the economy.
I also reckon compulsory voting, or pay £10, your choice.
A friend of mine, who is pretty much the lefty version of me also reckons a cap on number of terms served is needed, I'm not so sure as you'd loose experience. He argues its an end to safe seats for life, which I can see as a good thing.
Polotics used to be something you moved into after you'd earned some life experince. At current its generally a career you enter straight from university.