I don't know.

For one thing he is a big component to pull.

Yes his input only exists to pull Kenobi away so he cannot get in the way of Anakin finally flipping but if you remove him entirely you end up with a very short film which isn't dramatically improved.

If he could be adjusted to be a more constant threat in the series having Obi-wan take him down would have more impact.

It might sound hokey but combining him with Maul would go someway to justifying his presence in the film.

Dropping him into Episode 2 would help as well (he could replace Fett and/or Poggle on Geonosis).

Re-dubbing his lines could make him more important and less of a minor boss battle character.

If only Dooku remained a Jedi and the other guy was the real Sith apprentice that Vader replaced.