Now that witches are neutral, something needs to take their place in raids. I'm not going against witches being neutral because I actually suggested that but anyways:
Pillager Alchemists would not be witches but would basically be a cross between a vindicator and a witch.
They carry a stone sword and only use helpful potions on themselves and other pillagers. They typically stay behind everyone else and only fight when they need to.
These alchemists will throw weak potions of speed or regeneration at pillagers to help them out. When the time comes, they will drink a strength potion and attack the player only when everyone else has died. If the player kills them as they are drinking the potion they will not need to worry about their attack.
They will never actually attack with potions and only buff.