Glowstick:
Pros: super high damage reduction
6 damaging pools
High damage happiness bonus
When the shied is active and you take damage some health is regenerated
Passive stun doesn't happen often but when it does it last a awhile on the enemy

Cons:AA doesn't last very long
Shield isn't stun resistant
Happiness doesn't give a lot of health and armor

Nekro:
Pros: Shield IS stun resistant
50% to Terrify(stun) enemy on activating AA
good all around happiness

Cons: lower damage reduction
no damaging affect from the AA


There's the facts but the decision is yours, I mainly do pve so in mausolem I prefer Glowstick, but the stun resist of the nekro might be better because of stun resist, I feel like Glow would be more of a hit and run pet (with speed set) which you can't get at lvl 17, but again its up to you