Spells aside, I'd say that gnomes are a slightly better option: gnomes have the better saves, possible 18 Con, +3 AC from helm, and +1 Int vs. the elves' +1 with bows/longswords, possible 19 Dex giving another +1 to hit with bows, charm resistance, and max 17 Con.
Spell-wise, it's about your party composition. Do you have another caster? How good is that caster; is it a bard, another specialist, or multi or dual classed? If you have a good second (and third?) option within your party to cast the necromancy spells, then the party isn't hurt by having a specialist instead of a generalist as a melee mage.
Edit: of course, having an illusionist filling the F/M role means you will probably never use spells like Ghoul Touch and Lich Touch. Does that bother you?

Chill Touch, too - a nearly worthless spell...
[ 02-02-2006, 03:33 AM: Message edited by: Aerich ]