I've done 6x rank 4 quests and have gotten a total of 2 SSR drops. I've also done 3x rank 3 quests and got 1 SSR drop from that.
I didn't have time to post my experiences with the Wind and Light element quests, so might as well do that here.
Wind element trash all uses ATK buffs, and so does the mid-boss. Strong DPS is highly recommended. Since my DPS is weak, I brought along AoE combo attack down (Triton) to prevent lethal combo chains, as well as Dispel. Ironically, I went into the final boss without debuffs and the boss promptly triple ATK KO'd a kamihime.
The bottom Light element trash uses AoE poison, while the center uses a straight AoE. The top uses a 2-hit single-target attack which isn't too threatening. The mid-boss uses an AoE that prevents healing. I had Poseidon and Gaia, so I had a hard counter for all of this.
I've started holding Mordred's Outrage on the final boss unless I need it to supplement a Sniper Shot miss. This allows me time to refresh my 7-8T CD debuffs, even with the lag between turns, and prevents an unlucky Dizzy proc from causing Gaia's damage mitigation to miss. As long as I can keep debuffs up, I can reliably clear without elixirs or even deaths.
Sounds like your Light team has more DPS than my chimera team of Mordred (Sniper Shot), Poseidon, Gabriel, Gaia, Sol. Final boss takes forever to kill. I think I eat somewhere around 4 raging overdrives. Maybe more? The upside is that the team is basically invincible when debuffs are up.Took one raging overdrive and without Joan's damage reduction. It did 7-8k damage with the same debuffs as above up, on 3 random himes, hit my Balor twice and Satan once. It took out my Balor and almost took out my Satan, had less than 100 hp left. Though by then it was nearly dead so my team more or less cleaned up with a couple turns of auto attack.