Not for miracle tickets (since I ended to be F2P), but a related question:

I have a non re-rolled account with the following KH

Fire: Ceridwen, Amon, Agni, Baphoment, Hestia, Ignis, Dazbog, Nergal
Water: Nodens, Kikuri-hime, SR Nike, Apsara, Dagon, Oto-hime, Rusalka, Undine
Wind: Cybele, Maeve, Boreas, Puck, Zephyrus
Thunder: Thor, Baal, Nemesis, Indra, Verethragna
Dark: Nyarlathotep, Mephistopheles, Naberius
Light: Metatron, Aurora, Orpheus, Urania

Gacha SSR eidolon is Behemoth.

Is now (holiday gacha) a good time for me to roll gems? Or is there a release bonus that I should be waiting for that would significantly improve my team?

I think my best teams are water (double healer, but my heals are starting to get outscaled) or wind (double attack down, run either full wind or Lilim Luxuria, Aurora, Nyarlathotep) but one good SSR could probably change that. Rolling sooner gives me a higher chance of getting core SSRs like Sol, Gaia, Amaterasu before they get further diluted, so I don't think I should hoard gems, but should I?

Bonus question: have D'Artagnan and Mordred unlocked. What Soul should be next, for your recommended configuration? I'm thinking Joan... she seems to be recommended for a lot of bosses.