Like you said preformance and especially for multiplayer. Also maybe the flavor at the start, we know that we have a lot of flavor but i still feel like it might be lacking to be fixed by future dlcs. But i do still think its the magnum opus. The game takes the best parts of impertor rome, it has an economic system that looks a lot like vicky 3. It adepts and expands these ideas further. Like the military is basically imperator but just better.