Death damage boosts against balance type enemies solving the problem of balance not getting converts. Death wizards are also known for drain spells which can solve the need for a life wizard. Death also gets access to feints to make your balance friend a monster on the battlefield. Death also gets spells like doom and gloom, so if you decide to PvP after finishing the game you can doom and gloom while balance takes care of destroying the remaining wizards. If you need to fight a balance boss the balance wizard can blade you while you prepare to hit. Darkmoor will also be a breeze because of the fact that death wizards gets Call Of Khrulhu to sweep enemies while balance gets Gaze Of Fate for fighting bosses like Tatyana, Shane Von Shane and other bosses really (except balance bosses). But don't worry on relying on your friend to fight bosses. Death wizards get Winged Sorrow to deal with balance bosses.
My main wizard is . I often play with my friend whose main wizard is . We seem to complement each other well. We have also played a combo, but those wizards aren't very high level yet, so I don't know how that duo will do late game.
You might try a balance wizard yourself. Balance with any other school is basically asymmetric, balance can easily boost any other school with extra blades and whatnot but it is difficult for any other school to boost balance attacks. With two balance wizards you can trade off hitting and boosting, but with balance and a different school that doesn't work well.
Death:
. I often play with my friend whose main wizard is 
combo, but those wizards aren't very high level yet, so I don't know how that duo will do late game.