The equation is simple: Higher FyrePower = Better jobs!
Your FyrePower is an indication of your overall performance as an influencer, so with a higher FyrePower comes better opportunities.
Some contracts and jobs may require you to have a certain amount of FyrePower. If yours is below the required level, you may lose out on opportunities. As you grow in FyrePower, you will see the number and relevance of the contracts improve to better suit your needs.