Heroes with Miracle Question

I didn't get anything from the Legendary Banner unfortunately. So, my next focus in the meantime is on the Heroes with Miracle.

Out of the three heroes on the Banner, I only have Sigurd (Probably the best out of the three imo). It's a +HP -Speed Sigurd, but he's been performing exceptionally with Attack Smoke 3/QR 3 seal.

My main question is around Delthea and Mist.

I REALLY want Delthea since she's strong, has Dark Aura, and she has good Res too! Also, I like her as a character in Echoes and in heroes too.

Mist might not be the best healer in terms of stats (with the small exception in her attack (because superboon) and her Res), but she has really good tools for a healer. Slow+ is pretty good with built in Speed Smoke, Miracle of course, and Recover+ which is the best healing assist in the game. She also has Spur Def and Res which is good, but Male Morgan has that too and he's easier to access.

I do have a +Speed - Def Linde already with Dark Aura and I have plenty of other healers like Elise, Bride Lyn, and Lucius.

I don't have Mist and Delthea in the catalog and I might want to build them up. I do have skills for them like Draconic Aura and Desperation for Delthea and a couple of good skills for Mist like Speed +3.

Is it worth pulling for Delthea/Mist or wait for Thracia?

Please let me know your suggestions! Thanks in advance!