Troops vs magic, what am I doing wrong?

[sector24]

I do play on 300 supplies, but the really large armies still starve if they province they are sitting in doesn't have enough population. I guess I am an anomaly, or I've just been using nations with powerful PD. The worst things for PD to have is low morale, and/or flyers. So Mictlan, Caelum, the giants, etc. are going to get rolled eventually. But most human nations do fine: T'ien Ch'i, Eriu, Ermor, Pythium, Utgard, etc.