A few comments about general class skills
-I find the idea of the barbarian possessing a Knowledge class skill to be a little strange, and I think Survival covers the sort of familiarity with the natural he would possess. Stealth would be a more appropriate skill, I think
-As druids are priests of a sort, they should have Knowledge (religion) as a class skill
-since fighters are involved in armies and often serve as guards, and, for that, matter, secular knights are generally fighters, they should possess Knowledge (nobility) as a class skill. It’s a more pivotal Knowledge skill for them than Knowledge (engineering) or Knowledge (geography).
-Knowledge (religion) should be kept for monks. If nothing else, there’s such a strong link between the class’ name and religious knowledge.