@Darielle - yes I've enjoyed good success with the quests too. I admit that I used the Chests tab in TomatoeHu's sheets rather than think the "Best for Grand Prizes" selections through for myself.
As a Spire negotiator, I definitely want the second Astral Phoenix too. I have never bought the Stash Hut and was in two minds about doing so this time. Its good to know you had success with the Hut.
As it is I will likely use diamonds on the last day to make up the shortfall for the second Phoenix. (there will probably be a short discount period for buying game tokens on the last day). I've never done that before either, but fortunately I have accumulated a good stash of diamonds.
If you have already got the second Phoenix you will likely finish in at least the Silver league. That will earn you another artifact. I think the FA does typically award two artifacts as well, but you never know.