Yeah, the classic campaigns were made with the 18 original civs in mind, balanced around them and with restrictions of that time(limited pop, one UT, etc). The developers have been updating them with the new civs and new content ever since, but I feel the difficulty hasn’t been improved.
The new Legendary difficulty is a good excuse to improve the classic scenarios; however, unless it’s paid content, it would take quite some time before they’re added. I have no idea how difficult it would be to make such improvements; perhaps it’s more beneficial to create a campaign from scratch rather than constantly updating the old ones.
I would prefer that they add campaigns for the civs that don’t have them yet and then start remaking the classic ones with more historical accuracy (balanced with good gameplay, of course) and making them different enough to be part of a new DLC, while at the same time preserving the classic campaigns under a special tab (Legacy Campaigns, perhaps).
adding a “hardest”, “extreme” or “legendary” difficulty on top of the existing ones, is exactly the kind of change I want to see in a definitive edition. it leave the original intact while adding options on top of it
Admitedly, the way this could be implemented is up to interpretation. Theres many old “easy” campaigns who are still fun (Barbarrossa, Attila, Genghis Khan) while some are just wayy too easy (Joan, El Cid). So, would the very easy campaigns have a bigger jump from the existing dificulty than the other ones?