A new class doesn't have to necessarily fit a niche. You can have multiple DPS/Tank/Heals classes that are either ranged or melee. Just to use an example, WoW has rogues and druids. Essentially the same class but totally different "flavor" and mechanics. Personally, I'd be happy with engine upgrades. Maybe fix the textures. The difference between the animations for the new content vs the original content is like night and day lol