a really small thing that bothers me is spatial.setCullMode vs CullState.setCullMode which has caused some confusion to people i know. i guess cullstate.setcullmode(front/back/none) is what you ususally mean when talking about it…but how about spatial.setFrustumCullMode or cullstate.setCullFace?
but maybe noone cares and it's just more work than what you get back 
If we make a change, changing CullState would seem least disruptive. So maybe the CullState.setCullFace? Would be more descriptive of what is going on there anyhow.
as i said, it's a small issue, but even those can stop jme-noobs from hanging around