well if you dont wanna target for the mage's blizzard, you can spam arcane explosion, on the same key as paladins consecrate (its what I do) I just spam that button when i get a lot of easy to kill adds, or i dont feel like targeting.

I also made a macro on my paladin:

/targetenemy
/castrandom Avenger's shield, hammer of the righteous, consecrate

on the same key as my mage's

/castrandom [target=focustarget] [] Fireblast, Ice Lance, Arcane Barrage

I just spam that to finish stuff off, or whenever I am running, or repositioning for boss/tough mob fights. It's basically like tabbing around, but simultaneously, my mages attack. Then I find the weakest mob and finish him off, etc etc.