Alright, I started playing this back in the day, but picked it up like last month.

My current teams are as follows:

Fire:
SSR Beelzebub (fire)
SSR Mars
SSR Uriel
SSR Amaterasu

Eidolons for fire kinda shitty, Fafnir/Crom Cruach being only two of note really

Water
SSR Ryu-Oh
SR Oceanus
SSR Raphael
SSR Nike

Eidolons: again kinda shitty, just the basic epic quest ones

Thunder:
SR Tezcatlipoca
SSR Jupiter
SR Astraea
SR Baal

Eidolons: Kirin/Girimhelka (i pulled Kirin yesterday) This is one of my weaker parties, haven't put anything into it

Dark:
SSR Nefertem
SR Meretseger
SSR Kali
SSR Osirus

Eidolons: Anubis

Wind:
SSR Azazel
SSR Hastur
SSR Gaia
SSR Cybele

Eidolons: Behemoth and then epic quest eidolons

Light:
SR Anteros
SR Hermes (light)
SR Mithra
SR Artemis

Eidolons: epic quest ones

Which party should I focus on? I also have SSR Diabolos if that makes a difference.

Soul wise I have been using either Mordred, Arthur, Solomon and am in the process of leveling D'Artagnan, and as soon as I hit 200 SSP I am going to pick up Yukimura.

In terms of gameplay wise what should I be focusing on? Each element party is at 30k+, what am I missing to go take it to the next level?

If there's any more information needed, please don't hesitate to ask.

One more question, rare weapon farming, besides gem gacha, are there any quests that reward rare weapons that's worth farming?