One small thing, I personally dislike summons that have a hidden gold cost.
Apart from that, I think you can win with only 2 provinces, one cap, and the other to dump all the unrest creating temple burning commanders in another province. Fort that one up. Get gold from events, and gather all the gems and slaves produced by the commanders

.
The freaks expand perfectly fine. Immortal, and berserk. Ideal to destroy anything that comes into your lands.