Unleash hell again? - When are pointless sequels too much?

[Arthur Dent]

Setting a story in the same "universe" as the first could work, but they shouldn't call it "Gladiator 2". Or even have the word Gladiator in the title. Do something about one of Maximus's liutenant's becoming a general and fighting the Celts or something, but don't rehash the original with some new noble gladiator character.