Power Buildings

To be honest, I only played the original game (without any expansions), so I don't know how I would build my army now. But I remember that I always tried to get a harpy, a cyclops, and a bird. Of course, the nomad and the monster are stronger, but the bird is much more mobile (+the lightning strike sometimes helps), and the harpy has a retaliatory attack, which can be very useful in battles (especially against neutrals).
PS. I recently downloaded Equilibris, and as soon as I find enough time, I'll try it out and see what has changed.