Join Date: Jan 2009
Location: Worcestershire, UK
Out of those choices, from a gaming PoV I would say go for Dark Elves.
VC are a challenging army to play; their rules/army don't really work with the new game rules so they aren't as powerful as they once were... the same is true of Brettonians but to a much greater extent since they are meant to be cavalry heavy and cavalry get nerfed almost to the point of uselessness.
This is not to say they can't win- both have strong lists and in the right hands are very daunting foes... but its hard to learn how to play/win with either.
HE are my 3rd army... but I never play them. I just never got the feel for them: their units are weak but powerful; capable of winning, but are so very fragile that a few bad roles or a little enemy shooting/magic and your unit disappears. They are a good army and their magic is some of the best around, but don't rely on their shooting: S3 archers are pretty poor and bolt throwers really suck in the new rules.
DE on the other hand have everything. Their magic is devastating, they can pump out enough shooting (even at S3) to hurt almost anything, have solid combat units, cheap infantry, one of the best monsters in the game in the hydra (I think it is the best) and excellent fluff. However... you have to like the style of their fluff. If you read through their story and don't like the army you'll never enjoy playing them as much as you might.
On the table they can be as fragile as HE, but with cheaper models and the ability to counter most enemies (or just use assassins to confuse and mislead.. then kill) they can be immense.... but if you don't co-ordinate your army into 1 combined force you will lose, a lot.
Mostly I think that armies should be picked based on fluff, models and playstyle. If you like all 3 then its a good match for you. The first 2 can be circumvented by either creating your own backstory and/or re-modeling... but I wouldn't advise it for a first army.