Kella is actually pretty useful. Is it possible to change her narrative so she can be recruited by someone other than a druid? I had heard that a true neutral character can do it as well. But I have not had any luck with that. It makes sense that she would help a good party, at least. If a team has come to destroy the people she is spying on..why keep spying?
Kella can be recruited either by a PC druid or by any PC in a party that has a True Neutral party alignment. The original pencil-and-paper role-playing module states the following about the half-elf Kella:
Given the change in alignment restriction for druids (must have one neutral component, rather than TN only), might it make sense to relax the original module rules a bit? I have to say I never recruited Kella to a TN party, while two druids is a bit redundant.
Scratch that, finally managed to read gazra's original module Kella info, which makes no reference to alignment (so the TOEE rules are 3.x-aware). Still, I think the point stands that few TN parties that are druid-sympathetic wouldn't already have a druid, and the original module seems to have Kella happy to support a Good party if it's obviously opposing the Temple's power.