Is the UPPSC worth taking after failing in the UPSC?

Yes , definitely. As per the official notification of UPPSC , commission has changed its syllabus & it is now on the lines of UPSC. So you don't have to prepare separately for UPPSC if you have already prepared for UPSC . Some extra things you have to prepare for UPPSC are:

  1. UP static gk
  2. UP current affairs
  3. Census - India & UP