I would put caps on each country. I would personally accept more people from Europe, US or Australia. But be more strict on other nations especially muslim nations for better culture compatibility

Here's an idea.

Anyone can get a visa, but must pay 1k per month for each month they stay here, plus a deposit to cover costs incurred if they overstay their visa and need to be forcibly removed.

5k/month if you plan on earning any money while in the country (working).

Citizenship only if you work in the country for 5 years (300k total cost), at which point you may bring your wife and any biologically related children.

Otherwise, a citizen can bring any ONE spouse from outside the country, and only once in a lifetime, who will remain on a PR for 15 years before being eligible to be a citizen. In the case of divorce, the PR is lost, and they and any children they had must return to original country.

Existing citizenships (for adults over 18) can be sold on the open market for an 80% discount (not re-transferable after it has started) on a working visa. Saving 240k. This is done to get rid of the lowlife faggots - hopefully - before they breed.

Profit from this program is immediately repaid to the citizens in the form of tax reductions across the board.

Find a flaw.