in movies we have
- empire strikes back
- adams family values
- blade 2
- robocop 2
- conan the destroyer
- terminator 2
- evil dead 2
- dawn of the dead
- mad max 2
- godfather part 2
- batman returns
- lotr return of the king
there are others. and im not saying all these movies are supirior to there first parts. but they are at the least equal and in some cases they are supirior.