I really don't know what it is about Agartha... If it's just because they're an original idea so far removed from the commonplace orcs and elves, or if it's the heavy backstory and theme applied to the nation, or if there really is just something innately attractive about olms weaker nations. Whatever the case, I do very much like playing as them.
So much so, in fact, that I keep trying out new strategies on them. The imprisoned olm water/earth bless strategy is going so-so, the ignore-Agarthan-troops-completely-and-pretend-you're-Ermor ghost king SC is falling flat on its face, and the forge lord minor bless ended up being a little lackluster as well.
Well, time for something new then.
I just tried out something a teensy bit different... I happened upon a guide for EA Agartha that talked about the Ancient Lord thugging capability. The guide was, however, written by HoneyBadger, a person whose advice I would not rank very highly... But it did get me thinking.
Enter Alahrim, the Risen Oracle. 9 Earth 4 Death, 3Turmoil/3Sloth/3heat/3Death/3luck/3Magic, Dominion score of 9.
This gives me a helpful bless, while also giving me an awake SC. Who's immortal. With awe. And +4 fear. And 10 base protection thanks to the 9 earth.
While he was off spooking indies with his fear/awe combo and hand of death castings (he's still an Agarthan, so hitting people isn't one of his strong points), I sent off a couple ancient lords with the starting army, supplemented by a few trogs.
I've never expanded so fast. With anyone.
Agartha has got some rather interesting capabilities... For starters, they love castles. They love them so much, they work extra-special-hard to take them away from other people, and get a siege bonus. Second, Agarthans don't need to eat (I was always a little confused by that one, personally), so they can sit behind a castle wall for as long as they need. And the heat/death/high dom combo will shred the available supplies for any sieging army.
This brings me to the Agarthan special castle, the Cave Fort. I read somewhere that cave fort sieges will be fought under the effects of a darkness spell. I also read that this was on the bug list, for some reason.
I've never experienced it firsthand, but it seems perfectly reasonable that a subterranean fort would have the effects of a darkness spell going. It would also make it absolutely perfect for Agarthans, since they all have 100% darkvision, and the darkness would make everyone else suffer in the exact areas that the Agarthans are so commonly associated with (attack and defense).
Cave forts are still very expensive and time-consuming for what they do, of course... But with the rest of the Agarthan aspects, it would make for a defensive bastion that almost any enemy would struggle severely with trying to remove.
As for the scales, I think they're actually pretty good, considering the strategy... Death is almost a necessity, and with it you are dooming yourself to a late game fraught with low income. This is further compounded by sloth 3 and turmoil 3. However, since you won't be making large numbers of troops with a thug strategy anyways, and trogs only cost a single point each, sloth doesn't hurt as much as it might seem. Turmoil hurts, of course, but it also provides that delightful synergy with Luck. The fun thing about luck is that it can still provide you with a high (albeit inconsistent) income regardless of how many people you can tax. And if there's still a magic + luck synergy, then you'll still be able to find those 3000 gold treasures amongst all the dead civilians. Whereas order will only help you early on, when you still have a few people standing.
Furthermore, gems can be turned into emergency funds, and Agartha is primed for earth gem incomes, not to mention a reasonable access to fire. You'll generally have better things to spend gems on than cash, but it's still a consideration.
Also, the risen oracle is both thematic and awesome... Which is always nice.