So much of this depends on the context, goals and personal situation.

The answer won't be the same for a multi millionaire looking to spend his time working on a cool project or for a low wage worker trying to make it and quit a boring job.

If you already have financial freedom, i guess you should aim for the stars, as in go for something big.

I you're trying to reach financial escape velocity and get rid of your 9 to 5 job, you might want to try small ideas first as it should be easier targets and you probably only need one successful project to be free. Then you can go for the big ideas.

Ah .. I thought about this, but I've found that most people who have hit "financial freedom" generally tend to lose momentum and lose drive .. fewer of those actually end up building something bigger .. just a personal observation .. although honestly it seems compelling .. but unsure how it will affect me / my friend specifically