Well for starters, we need your weapons and your other himes you have available.

Solomon has been pretty much labeled the least necessary soul and pretty much obsolete other than leveling her for her mastery bonus.

Your himes are all over. You have 5 different elements... Focus one or dual element teams unless using a hime for a specific purpose. Amaterasu and Sol can be placed in any teams since they're used more for their debuffs/heal.

I have no idea who your main eidolon is as your party is clearly all over the place.

As for your goal, farm break limit materials from SP quests, they change daily. Aim to break limit all your SR/SSR himes you use to at least 3/4. Farm elemental Disaster raid bosses for SR weapons of your element, you unlock it after clearing the first zone. And do events, you don't want to miss out on SSR eidolons and weapons.

Luckily for you this event has no eidolon or weapon, you'll most likely miss out on the holy soul P but nothing you can't get next union event and eventually get so much it has no use.