So after finally doing a campaign with these in a team that was dedicated around bless/curse tokens, as well as seeing the new doom sidegrades like Ceremonial Sickle, I felt like it was worth evaluating this cycle of cards again as I think that merely saying "it's good with curses" doesn't really go far enough to describe. The Doom Charms are cards that also require some concessions in deckbuilding and playstyle, but even when you manage to really mitigate the downsides of putting doom in play, you end up with mediocre weapons that just don't really stack up vs the regular Spell assets like Shrivellingand Azure Flame. Their raw power just isn't very high to the point where even if you can manage the cost of having to figure out where all the doom is going to go, you still are left with cards that don't really pull their weight.
Armageddon (and Eye of Chaos) both have 3 big costs to them compared to the standard spell assets. Firstly, they're just less efficient than their base versions. Eye costs 1 more resource than Rite of Seeking, and Armageddon costs 1 more resource while also giving you one less charge than Shrivelling. Secondly, they require you to hit curse tokens to get any substantial benefits over the base versions. And lastly, the fact that you're hitting curses (and thus getting reductions in your skill value) has to be overcome in some way in order for you to still actually pass your test. Using these assets as an expensive way to hedge against unfortunate Curse pulls IMO just isn't really the best use of these cards, and if drawing curses are that big an issue for you and you're not going to invest in finding them consistently you should just have your party run less curses.
However, I think that of the 3 downsides, all of them can be reasonably mitigated with the right build. Firstly, the lowered base efficiency can be reasonably made up for if you consistently hit curses. If you hit a curse on even 2 tests I think you break even vs Shriveling as you can give yourself 5 total uses or potentially get a clutch extra damage that you can distribute among any enemies at your location, allowing you to either kill a 3 health enemy clean or deal 2 to one and finish off another. If you consistently hit curses, you can pull well ahead of the vanilla versions. Shriveling and Rite of Seeking will eventually run out of charges and force you to find and play another copy to get uses back, (or some other card that restocks the charges) but Armageddon and Eye of Chaos can easily last the whole scenario with no support outside of making sure you find curses, saving you resources in the end.
As for actually hitting curses, you have 2 fairly effective options. Favor of the Moon can give you a curse on demand, although only one a turn so it's somewhat limited but still extremely potent as it alone gives you 3 guaranteed hits. And secondly there's Olive McBride. Digging 3 deep for tokens gives you a pretty good chance of finding at least one curse if the bag is stuffed with them.
For actually passing tests that you reveal a bunch of curses, there's a couple massive bonuses. Firstly, there's the Blasphemous Covenant and False Covenant which both mitigate the negatives of them. But the really big bonus is the newly buffed Ritual Candles. This card is absolutely nuts with Curses and Blesses as it gives you the boost for each one you resolve. Even one of them can go a long way in more or less mitigating the fear of drawing curses, but if you can get 2 in play it completely cancels out the curse penalty making them all upside as you remove them from the bag. Unfortunately, Mystic as a whole isn't the best at finding non-spells consistently so if you don't find your candles early it can be a struggle to pass tests especially if you don't have any other sources of Willpower boosts, but if you can find them it's extremely strong.
So the sort of TL:DR is that if you can support Armageddon and the other Curse spells, they're not just fairly decent. They're absolutely fantastic and greatly reward you for building around them. This is sort of a thing that you unfortunately kind of have to build your entire team towards supporting, but it is fairly effective and fun to play with, and since you'll be pulling curses with Favor of the Moon and Olive, the curses will be in large part mitigated by you so it's not even that bad for your teammates.