When I defeated the Necrophage armies, I had my entire army concentrated against what were mostly garrisons, and I suppose some kind of reserves? I didn't see a Necrophage hero until it was all over, and in the initial battles against the defenders of Saradh they came out from their defences needlessly and tried to fight me across a single hex chokepoint that negated their numerical advantage. If they had just waited inside the city and brought over a few more armies, I very much doubt I could have taken it. I don't expect AI in strategy games to be able to brilliantly handle these kinds of situations, and there's an undeniable thrill in defeating a superior force thanks to decent tactical play and poor AI decisions (the Total War series is also good for this). Still, it does mean that this military chart is not quite accurate because it doesn't take into account the advantage I have from being human.
Later in the game when most of my villages were full, I could have raised probably something like 20-30 units in a single turn if I'd wanted to. It would have tanked my economy, and some of them would be weak support units that couldn't form a fighting force on their own, but it's a real strength that I don't think I fully exploited in this game. I was also lucky that generally I got friendly with most people so that no-one was raiding and destroying my villages, otherwise I would have needed to station armies in the areas far from Citadel to protect the most distant villages.
I was going to include more words here about how I actually felt while playing the game - what parts were fun, when was it dragging a bit, and so on - but just talking a bit about each of the graphs has already ended up being a pretty large post, so I'll split that stuff out into a separate entry.