Out of the pre-made Sovereigns, only one is something of a traditional Wizard. The rest are more warrior type with backgrounds like Miner or Thief. Now having a warrior sovereign is cool but I have to wonder..

The title of the game is War of Magic. In the beginning the Sovereign is already a powerful channeler with the ability to bring life back into the barren land. Does not sound like a small feat by a longshot. With that kind of power I would expect them to have other knowledge of magic as well instead of being just a soldier. What about later on when global magical warfare steps in. Won't it be much more important to have a powerful spellcaster Sovereign than one that has a high strength or few HP more?

A Sovereign like Sauron with massive melee power would be cool. But surely that could be achieved by magical might rather than putting points in strength and dexterity? In fact I would like to see any superhuman abilities gained through magic and sustained spells rather than just boosting your abilities leveling up. So it should be more about Essence and shard control than physical attributes.

It just seems to me the Sovereigns are so far above the power level of ordinary humans and that mundane skills are insignificant compared to the magical powers they can wield.

I could see myself picking a "Warrior" background trait/feat for my Sovereign to make him a skilled combatant but rather focusing on the magical aspects of his development after sovereign creation - to wage the War of Magic.