So far, I've tried this, but it doesn't see to be working - new buffers still start in normal mode. I'd prefer to default to evils emacs mode, and be able to switch into evil with C-z when I'm ready
(setq evil-emacs-state-modes (append evil-normal-state-modes evil-motion-state-modes))
(setq evil-normal-state-modes nil)
(setq evil-motion-state-modes nil)