I agree with everything except,

> Don’t add a co-founder after the fact

Late co-founder makes a lot of practical sense to me.

- It's less risky for the incoming person to join a small profitable company instead of joining an idea

- You broadly know the problem space you will be working in (market, customers etc.) and the vision/direction of the company. Less likely to have fallouts a year or two down the line

- More informed equity negotiation than just splitting it equally