The design is done when the problem goes away.
It's simple until you make it complicated.
Projections are just bullshit. They're just guesses.
Before you dismiss a beginner's work, remember how much you sucked when you started. You probably sucked worse, actually.
The only two people who can give you real feedback about your product are people who just purchased it and people who have just canceled.
What matters is: Are you profitable? Are you building something great? Are you taking care of your people? Are you treating your customers well?