Regarding electoral systems, I'd choose PR over FPTP, because PR suits my political aims at the current time.
Despite this, I understand the benefits of FPTP as a system, and I can see why a country with a long-running and mature democracy (like the UK) would want it. It's important that political parties are forced to develop a long-term record, and credibility. If we ditch FPTP, then single-issue parties will come and go frequently, allowing bad politicians to go somewhat unchecked.
In terms of corrupt financial systems, I think you need to read up on some history if you think the UK has the worst. Sudan, Somalia, Syria, Afghanistan, North Korea, Yemen, Zimbabwe, Venezuela, Russia. And of course, the US, whose regulatory failures, speculation and novel (AKA sketchy) forms of debt caused the World's largest economic shocks in both the 20th and 21st centuries.
