Dear Don't want to sell out.
This ain't going to be easy for someone with principles. On one hand you might be able to be the vehicle for genuine input for outside advocates and experienced providers who have really good suggestions. On the other hand you might be setting yourself up to be a flak in charge of bringing in those same people for a cuppa coffee in order to help them try and understand the difficult choices that your boss has to make sometimes. Have an honest conversation with your prospective boss about your worries, and set up an internal process for measuring your own abilities to absorb the inevitable compromises you'll have to accept. Can you keep taking that big paycheck if you have to explain away only three stupid decisions out of ten. Five out of ten? You can sell out at any price you choose.