Step 4. Basically, once you have your e-fund set, higher interest debts paid, etc, you then decide how you want to invest for retirement.

Most people go for the 401k + IRA + brokerage account option and plan to use strategies like a Roth conversion ladder, but once you clear the basics, the world is your oyster for whatever passive income strategies you want to try (e.g. real estate, hard money lending, etc).