Very confused right now regarding Stellar Swirl...

(This is not a simple question, please don't remove!) I am thinking of doing this, so correct me if I am wrong:

A. Yumemizuki Mizuki:

1. Currently she is level 80/90 (Thinking of upgrading her to 90/90 after building Odette, is level 90 important for her?).
2. Will use R5 The Widsith on her.
3. Currently she is C0, will get her C1 and C2 from 7.1 Anniversary selector and Temper Thyself event.
4. If I am going for C2, then what will be the best artifacts set for her? Thinking of farming new set (Scarlet Proof) for her and giving VV to Sucrose (already have EM/EM/EM VV on her) or Faruzan. If I gave VV to her then I have no good Instructor set for Sucrose. (Also EM/EM/CRIT Rate substats for Mizuki artifacts, this is my plan).
5. Talents will be E 9/10 and Q 6. (Is this ok?)

B. Odette:

1. Will get her to 80/90 (Thinking of upgrading her to 90/90, is level 90 important for her?).
2. Will use the new craftable weapon (Emberwell) or should I make my first Finale?.
3. Only C0 as I am F2P.
4. New set (Heart of the Furnace) What will be the stats?.
5. I don't know about Talent levels (heard only E was important).

C. Sucrose:

1. She is 81/90 so same question level 90 needed?.
2. Will use Sacrificial Fragments R5.
3. C6 but I heard constellations don't matter in this team.
4. Artifact set is VV with EM/EM/EM. She is 885 EM rn.
5. Talents is 2/5/5 (These are not important in this team right?).

D. Traveler

1. He is level 90.
2. New 5 star weapon for Traveler (The highest refinement possible for 7.0).
3. Highest constellation possible for 7.0 .
4. Artifact set is ToTM (What stats?).
5. Talents levels no idea what is best for Cryo?

E. Faruzan (Should I replace Sucrose with her?)

1. She is 81/90.
2. Using Fav Bow R5.
3. Have her C2.
4. Artifacts set will be VV right? Can sucrose's VV fit her (EM/EM/EM one)? Or need to farm new one for her? (What stats for the new one?).
5. Talents currently are 6,6,8.

Sorry, if this is a long post, thanks for reading!