1st one: Nope, don't think anyone here would dispute that, except on the grounds that it's rather nonspecific.

2nd one: Only if it were in the form of encouraging particularly valuable individuals to reproduce more. Removing even the bottom 50% would have fairly negligible effects compared to doubling the top 1%. Several countries already implement programs to encourage the most valuable members to reproduce more (with mixed success).

3rd one: I find it nearly impossible to find any good data on that either way. Pending evidence, it looks like most of the quality of life and education effects can basically be explained by looking at who got the industrial revolution first. Unless very large effect sizes were found, however, the policy implications would be minimal or nonexistent.