They got their cost lowered from 13 to 10.
So?
They are simply the best in their price category.
13 morale, 11 attack, 14 modified defense and a mapmove of 2 matters.
Wouldn't call it a game winner, though.
You're going to want at least a -few- temples anyways, so it's hardly much of an additional cost to the sacreds, more of just an increase in overhead costs of running your nation.
Beware, the Kohen do eat pop. They aren't as bad as Melqarts, but it's an obvious effect.
Honestly I think that Gath is a nation that can skip the major bless. Throw a few good minors down that all of your sacreds can benefit from, and you'll likely be in great shape (remember you have sacred summons, as well).