What would your ideal army look like?

I would personally prefer Necropolis and Inferno. Of course, I would make some changes. I would take skeleton archers, Cerberuses, Inferno archers, a Lich, Death, and an Archangel. :))

Added 2 minutes later

There are no weak castles; they all have their own advantages.

And disadvantages too; we shouldn't forget about them.