Most on-line brokers are set up to do cookie cutter, W-2 income-based mortgages. I work with brokers I know, and they beat the on-line people every time. If your situation approaches cookie cutter, a good benchmark is Aimloan.com. Their rates are consistently low.
If your net worth is high enough, sometimes the wealth management departments of the banks can get you lower rates, if you transfer seven figures of assets to them.
If you are successful, telling your story may be helpful to others in your position.