Developing a Necromancer hero.

Usually, I develop:
1) Summoning magic (whatever comes up).
2) Logistics (again, whatever comes up).
3) Luck, resistance, and soldier's luck.
And for 4 and 5, whatever comes up, but I usually try to get chaos magic and vehicle control.

Why would Necromancers need Soldier's Luck? What's the point of investing in luck just for the Shield Bash skill of Bone Throwers, considering its 2% chance of appearing?
And why would Necromancers need vehicle control? Their ballista is weak, and the catapult? - what's the point, it's better to have Earthquake, and the first aid tent - again, raising the dead is much more effective.

Lately, I've been preferring Attack with Battle Fury/Magic, Speed, and Defense with Endurance/Evasion, because Necromancer troops are somewhat slow, and it's difficult to reach the archers quickly (of course, if there's no Mind Control).