We don't have FPTP, for GB elections we have plurality, the candidate in the constituency with the most votes wins.
French elections have a post (50% turnout plus one) that you have to be first past. That has worked well in the fifth republic to allow (normally) a second round run off between the best placed candidate from the left and right.
And to talk about 'paying off the deficit' is just nonsense. The deficit is the growth in the national debt. The best way to pay off the national debt (and which the good Keynesian economists out there would recognise) is to do so when your economy is growing and there are more taxes coming in from workers and less benefits paid out to the unemployed.