Kendrick originally a wizard/rogue headed for arcane trickster became a fey-pact warlock.
Neara originally a mystic ranger became an artificer primarily because the party needed a leader.
Amaryllis converted to fighter since barbarian wasn’t published yet.
After PHBII was published, Amaryllis returned to a barbarian.
After Arcane Power was released, Neara converted to bard using the ranged weapon bard powers in that book. (Allowing the party to keep a leader, while letting her stay an archer.)
As an aside, in the original script for Wrath of the Immortals “Othar” was named Balthac which suffers from a case of unfortunate naming. (Why is left as an exercise for the reader.) So the party named him Othar, since my portrayal of Kelter was heavily influenced by Othar Tryggvassen from Phil Foglio’s Girl Genius