I'm on board with the Ethereal suggestions on the previous page, but I think that
Wild Riders should be the Ethereal component to our army. They desperately need something to make them cooler, and better. There are a a few different ways they could do it;
1) they're straight-up Ethereal (most expensive version; they function as a standard Ethereal unit)
2) whenever they complete a charge they are considered Ethereal until the start of their next turn (next most expensive version; they become a glass hammer that tries to win a combat quickly by stacking the CR in their favour)
3) they are Ethereal so long as they are not engaged in close combat (least expensive version; their conditional ethereality improves mobility and protects them from missile fire)
Another thing I would love to see are
Naiads. Forests don't exist without water. These could serve as the inevitable Monstrous Infantry choice in the new book. They could also be a scary and borderline malevolent monsterlike choice, as a previous poster wanted to see.
Hmmm, I hope this doesn't sound too rude, but the ironic juxtapositioning of those comments makes me think that you might not appreciate the implications of the fluff yourself.
We had a short, but good, discussion about the incorrect outlook some people have on WE fluff in
this recent thread. TL;DR version = Wood Elves DO and MUST have ranked infantry, otherwise their presence in the Warhammer world does not make any sense whatsoever.
Berserker Bears certainly live up to the rule-of-cool, but you're not going to be defending your meadow pasture heartland from an incursion of hardened Dwarf mercantilist-plunderers with them.