Id like to go out on a limb and say:

lol

Zombies can only kill you one of two ways:

The Horde

Sneaking up on you

Don't knit pick.

I fail to see how Zombies sneaking on you is such a huge advantage for necros.

A zombie sneaking out is a huge pain, but sneaking in?

Veteran players stack the move in with murder X, so that even if you notice him entering you can't quaff a vial fast enough.

As long as they can't hide from where you are fine. And necromancers with pets can't hide.