Well, it seems that there is some form of alignment left in the game, which doesn't really make me happy, but I guess I can still hope it is meaningless.
More importantly, while I approve of the idea of making fey more interesting and potentially dangerous, I question the sense in making dryads and considering about making unicorns into something for the PCs to fight.
Unicorns are one of the very few creatures that are unquestionably great to turn into a mount for a high-level PC. If anything, they should be rebuilt to serve in that role better, rather than anything else. The fact that Mr. Baker is not mentioning that role at all is worrying me somewhat.