The cool thing about the idea of another pseudo-historical film following Gladiator?
The idea of Ridley Scott making his own version of the Year of Five Emperors, or anyone of the half-dozen or so major Imperial Civil wars before the Western Empire fell.
The bad thing about the idea?
Making a film that pretty much has to start by revealing that the more optimistic ending to Gladiator was laughably inaccurate, both for the history that inspired the first film and for the world inside the first film.
That's one of the the few edges that The Fall of the Roman Empire had as a film covering the same type of ideas as Gladiator; the more pessimistic and tragic ending of that film could easily be followed by a civil war movie without much issue.