How about instead of make every race weaker and orc and faery stronger, we nerf the race from this age.... which imo is orc. Keep everything else relatively the same, but reduce orc gains and increase their military losses on attacks... keep cleric the way it is this age. Invincible offense should remain an undead only trait.
Orc/cleric is by far the strongest selection this age, and you have just made it stronger, while making every other selection weaker.
Faery t/m looks better, but lots of kds won't even run t/ms.