So, in my opinion at least, the new promo items seem like they'd fit nicely into Almire. Heck, the box itself kinda reminds me of the wooden crates in FSC.
So these new items look AWESOME right? But they're only costumes and reskins. Wasted awesomeness!
But here's something I hope Grey Havens could consider and use as an example for the future:
An event. Crazy, I know.

I think it'd be fun if FSC temporarily got changed for the duration of the promo. There are two ways this could go:

FSC of the past. FSC becomes temporarily restored to a past point in time, while Almire still prospered. The slags and guards would become Fire Raiders, Vog Cubs would serve as reinforcements, and Vanaduke would no longer be a towering fatso with an unwieldy mace but rather a hulking warrior with thought and intent behind each swing of his weapon.

The cooler path would be to make the citadel ice themed. Same thing, ice raiders replace slags and guards, maybe permafrost tails here and there, and Vanaduke would become the legendary father of the frost giants, Ymir.

In addition to normal Almirian Seals, the event FSC would drop Faded Banners, mementos of the olden Raiders.

These Faded Banners would be used to purchase materials to allow crafting of your ordinary brandish into a spicy axe, straight sword, or hammer!

Alternatively, you could purchase prize boxes containing the costumes and accessories (for loadsetokens, of course). The catch? It would only contain the Volcanic items, or Frosty if FSC was frozen over instead. The prize boxes could be divided into a costumes one and an accessories one as well, though having accessories taint your costumes pool is probably the only way to convince GH to add a "free" prize box.

I know it's a crazy idea that'd never happen, but one can always dream.

Also, something I forgot to mention: Hammer could've been shock troika, axe could've been a lovechild of cutter and spur, and sword could've acted like a rocket hammer with a stab on the first attack if they were actual items and not reskins.

TL;DR FSC gets reskinned to its past or an ice version with Raiders as enemies, and drops special tokens letting you buy materials to make the Raider items and buy prize boxes containing the cosmetics, but the box only contains the volcanic/frosty theme depending on which reskin of FSC.