So I've decided to make a necromancer. I know that early in the game a merc of either type is fine, but what about later on in the game. Warrior mercs could be good for some extra damage and holding aggro, but a healing merc will keep the pet alive for me. So which do I choose? The mercenaries are free when you buy them at level one so I'd prefer to make a good choice early and not have to buy a new one later.
In short: Whats better a tank merc or a healer merc for a Necromancer?