Difference between 'would+present' and 'would have+past participle' in these cases.
When John was 30, the doctor told him that he wouldn't live/wouldn't have lived past 40. Now he's fifty and his health is great.
Correct me if I'm wrong. In this case, I'd choose 'wouldn't have lived' because we know that John, who now is fifty, is alive and in good health. But if we where in a time when John is, say, 32, we would have to use the first, i.e. 'wouldn't live', because there would be still some chance that John wouldn't make it past 40. Am I right?
Mary moved to London because she thought a bigger city would increase/would have increased her job opportunities.
In this case, it depends. If I was writing a story about Mary, and I didn't want to reveal the outcome to the reader, I would use 'would increase'. So, in this case, we don't know if Mary would find a job in London or not. But if both I and the reader knew already that Mary did not find a job in London, I could as well use 'would have increased'.