Edited so everything is onto one topic. The rest of your topics will be locked and unlisted.
Your defense’s Priscilla needs a couple of things; Wraithful or Dazzle for B slot, a much better A slot, and a decent special… Putting Restore in her support slot wouldn’t be a bad idea ether; it may prevent her from running out in front of the rest of your team.
For your A skill consider Solo skills or Push Skills. For her special take ether Miracle, or a map wide buff that targets two stats. You’re also going to need to get her a speed boon if you don’t want her getting doubled, and killed on first contact.