Help with Rainbow Teams

Sorry another one of those help with my team posts.

I currently have the following defence team left to right:
Boldtusk, Rigard, Onatel, Tiburtus, Sonya

I also have the following attack rainbow teams set up left to right:

  1. Caedmon, Boldtusk, Onatel, Tiburtus, Sonya
  2. Gormek, L. John, Leonidas, Rigard, Kiril
  3. Red Hood, Kadilen, Richard, Quintus, Justice
  4. Rigard, Grimm, Boldtusk, Gadeirus, Wu Kong
  5. Melendor, Colen, Onatel, Proteus, Kiril
  6. Melendor, Elena, Thorne, G. jackal, Rigard

I also have multiples of the above AND other heroes ie
Elena, Anzogh, Wilbur, Li Xiu, Boril, Cyprian, Scarlett, Chao, Captain of Diamonds, Ameonna, Cheshire Cat, Gafar, Agwe, Skittleskull, Kelile and Hu Tao

So my questions are: (assume everything is maxed)

(a) is my defence line in the best order and can I improve it by moving any heroes in/out?

(b) are each of my rainbow attack teams in the best line order or can I improve any by moving heroes around?

(c) which of my other heroes not allocated to a team should I focus on next

Don’t worry about colour stacking etc, I do that when needed. It’s just that I have my teams set up as rainbow teams as a starter for ten.

Many thanks for any help and advice offered