Yay, I got around to this!
I didn't forget to get the money shot. Unfortunately I didn't do anything cool, other than main story quest. If the timing were better, maybe I could've maxed out by beating Garuda.
Speaking of, that happened! I wrangled together a few guildmates and we ran it. They were kind enough to only explain what I needed/probably should know and let me learn where I stand on my own. The one thing they did tell me was what to do during her OHKO move, which funnily enough I survived but my friend didn't because I guess she only reappears in one spot on the harder version.
The music in this fight is fantastic, I'm finding the primal themes to be the best in the game.
Defeating her caused me to acquire another crystal of light. I got the amber crystal from Titan and the red one from Ifrit. The rest of the crystals I believe I got from all the creatures I killed that were empowered by Lahabrea, my personal nemesis and member of the Ascians (they summoned Bahamut and nearly ended all life) who are arguably the main antagonists.
I also got to level 30 as an Arcanist and acquired the Summoner and Scholar jobs. I was gonna talk about the ACN quest line but I guess those screens are still on my PS4 so I'll just talk about it the next time I move that data off. I take all these screenshots and make gifs using the share function.