The terms you decide on can preclude you from offering a similiar product plus the new contract you signed. The fact that he mentioned wanting to control his d

The terms you decide on can preclude you from offering a similiar product plus the new contract you signed. The fact that he mentioned wanting to control his destiny probably means he wants total control over the project which could stop a similiar saas in the future. If you want to sell use a lawyer to handle interactions. Regardless of what you choose things can go sideways and your position might not be safe. So don't base it on that. If you don't sell he may try to replace it and you. If you do sell they may start treating you differently and the autonomy may disappear. Being the highest paid makes you a good target in the type of company you describe. The fact that he wants to buy the software now is a red flag that they are thinking of replacing you anyhow. I would say to the CEO don't worry you already control your destiny because I work here and I can't see that ever changing. We are a family.