I can see Sarah being a professional fundraiser.
She could pick and choose the candidates she wants to support, in the Primaries and in the General elections.
She would then have a national base of support to draw upon, for her own run.
She could make like Ronaldus Maximus 1976-1980. A lot of support for Republican candidates, and leading the charge on a signature issue, as did Reagan on the Panama Canal Treaty.
Palin will be fund-raising gold for conservative Republican candidates. Nothing like helping raise hundreds of millions to get strange new respect from the political class.