I think it's just curiosity, and I don't think you need to worry about being too demanding. What you're really after is a net increase in your personal happines

I think it's just curiosity, and I don't think you need to worry about being too demanding. What you're really after is a net increase in your personal happiness. I don't know your financial situation, but an offer with a much higher salary could very well make you much happier than you are now. In that case it would be worth looking into. Just make sure that you don't leave what sounds like a very fulfilling job too lightly.