Idea Kit Necromancer - Buffs

The kit necro as it is now will never be a better choice then something like engineer. A good kit selection panel should have a circumstance in which each kit is better then another. Like one kit being better for a specific map, or for assault or defence. Right now, necro is a weak version of engineer. I have spent time to think up some ways that necro could be made more balanced, playable, and fun!
NOTE: I'm not expecting all of these to be used, even if any, only 1-2 will make Necromancer a good kit.

Faster Spawning Mobs-
The rate in which the mob spawner creates mobs is too slow for a large horde to be born. The zombies usually
wander off or get sniped. A quicker spawning speed would allow a deadly number of minions be created. Making the spawner actually become a lethal threat to the enemies.

Smarter Zombies-
The zombies will never be able to catch up to an enemy. The enemy team could just run past the necro's horde untouched. I think the zombies spawned by the necro's spawner should have the AI of WarZ zombies. So they are actually deadly to the enemy. If you've never seen WarZ zombies, they are faster, stronger, and move in ways which make them harder to hit.

Multiple Spawners-
If the necro has multiple spawners, they could create a more focused population of mobs in a single area, or spread out their horde across the map. This might be to strong, even if any, they should only get 1-2 more then they have now.

Skeleton Spawners (?)-
Ya I know, this would be pretty strong. But skeletons ARE undead right? And necromancy is the practice of communication to the undead. Which includes skeletons. Either they necro could get a single spawner that spawns both zombies and skeletons, or they could get a spawner for each.

TP To Spawner-
The Necro's XP should fill up just like Elf's, and when its full. They can left click an item icon in their inventory to TP to their spawner. After they use this ability, the XP bar will go back to 0.

NOTE: I am not finished this thread, but this is what I've got done for now. Hope you like it!

 

I had no idea about the killstreak upgrades. 0_0 Probably because kill streaks like that are very hard for current Necro. I've never seen this before. But thanks for the feedback.
I have a few more ideas I will add to this thread around 5:00 PST. So if you're interested, check back then!

 

I see what you mean, where the enemy dies could become a skeleton turret?

 

So it would spawn a regular skeleton? With default behaviour? Still a cool idea!

22/6/15 Added another section.