If you've never tried a druid then now may be a good time, but if you feel that a bard or (multi-)class mage is more your style, then go ahead. Really, its a matter of taste, though I'd probably go for either of the two (mage I think).
You don't have to though, as you could carry on with five members and divide the xp without the hassle of another character. (Not everybody makes it to level 30 without some extremely hard work - its something to consider.)
BTW Would you tell us what levels your original party are at right now (he asks bearing in mind the level 14 xp cap). With HoW, you could quickly get a bard to level 11, then dual to a mage. Though, be careful with this, as the stat requirements can be a trifle harsh.
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Making running away an art form
[This message has been edited by Lord Brass (edited 10-17-2001).]