Pixies: innately invisible, with an interesting footnote. They can be seen clearly only when a spell to make them visible is employed, although certain monsters such as Dragons and high-level fighters will be aware of their presence. What is a high level fighter, we must ask ourselves. In light of implied upper levels of or around level 12, when does a player-character qualify as high level? Hero, Superhero, or Lord; these seem reasonable interpretations.
Dryads: these are highly likely to throw an overpowered charm spell and effectively remove a player-character from the campaign. Of course, a clever referee might use such an event as an adventure hook.
Gnomes: Dwarves Lite, all the taste but only half the calories. These like hills instead of mountains.
Dwarves: domesticate bears, wolves, or whatever to guard their defenses.
Elves: the description implies their ability to move unseen is the result of their gray-green cloaks. Which leads us to wonder if their talent for moving quietly is because of their boots? If so, a fantastic world might quickly become overrun with elvish cloaks and boots after a battle with elven-kind.
This description also gives us the elvish ability to split-move and fire but only while on foot.
Treants: referred to as Ents in the first printing. Treants can shepherd trees, making them men-at … ahem … trees-at-arms and obedient to the Treant’s whims. According to the description Treants are Lawful but are given some rather Neutral traits.