I don't have time to update it at the moment, but i've got a modmod in the works to make the barbarian trait less of a dead weight. So far i've changed the points based auto-declare war mechanic, but I plan to attempt some AI changes, and to add some kind of benefit to offset the research penalty (possibly race based rather than trait based, such as free goblins. I don't really like screwing round with the trait bonii themselves. Although charadon really needs another trait).
*edit*
the reason charadon and CoE tend to declare war on the barbs early on is because their AI is deliberately weighted to be more aggressive. Unfortunately the computer isn't all that smart- it pairs comparitive power ratings and attitude, and declares war based almost entirely from these. So it sees the barbs, notices their rather weak power rating/undefended cities in close proximity, and declares war. There needs to be an AI catch that prevents them from declaring war on the barbs full stop.