Hashut's Blessing wrote:
Personally, I think that Gildor's Household is a must have formation. They Ambush (which means they will be in defended terrain, upping their defence by between 1 and 4), they have elven cloaks (ca only be shot at when within 12"), longbows (to dish out some pain from within their cover) and 2 Wilderness spells per turn (a good idea is to use Guide Arrows to up the shooty damage and Nature's Wrath to do some direct damage, unless opportunities arise for the other spells that make more sense).
Having said that, Galadriel is pretty cool, but she seems more fitting for larger size armies (from a fluff point of view) and, whilst powerful, just doesn't seem to have quite as much oomph as a unit does.
Overall, I would suggest both, but Gildor first. It's personal taste. In fact, which models do you like more?
I donno, put Galadriel in a good combat formation, cast light of the valar and sunder spirit and enfeeble and you can watch your said formation reduce the opponent to a pulp. They will likely fail there courage test against your charge and so fight at F0, and enfeeble will reduce their strength as well.
To top it all off she can call a free epic action to either improve her focus rolls (with a re-roll) OR she can call an epic defence and boost your elves defence and therefore make them even more likely to sweep through your opponent.
Additionally she can support your other epic heroes with ease. She is a very very useful epic hero and at games of 1,500 or more I never leave home without her.