Retirement.

Run the numbers, then sleep at night.

Retirement math is really one question: how much can you pull out every year without running dry at 90? Bengen's safe-withdrawal-rate research gives you a starting point. From there it's sequencing — when you claim Social Security, when you convert to a Roth, which account you drain first — that decides whether the plan holds for 30 years or breaks in year 22.