Another idea
I apologize ahead of time because I am sure I'll get posts as to why this isn't feasible but here goes:
After fully reservicing it is there any value in sending the Hubble into Lunar or Martian orbit? Could we get a better view of them with the Hubble in their orbit? How about sending it to orbit Venus or Mercury? Would a view from the inner solar system benefit us in science and asteroid searches? Last, what about sending it all the way out to the edge of the solar system, the Kuiper belt, to take a look around?
Obviously such missions would take years, if not decades, to acheive their destinations. Could Hubble's instruments survive the deep space radiation?