It's a misconception that neutral conjies conjure worse servies than evil / good. They conjure the same strength servies. The problem with neutral conjies is that they've an almost impossible task of keeping their servitors happy. Basically, if you're not killing things and making your demons/devils/angels/archons happy you will be turned on. Neutral conjies are also the only combo that I've played that's had their own elementals turn on them.
The reason that neutral conjies suck bad, is that their cabal options are pathetic. Evil conjurers are only playable because of despoil. One of the nasty little secrets of evil conjies is that devils turn on them at 50%. A conjurer with 600 hps (average in mid-ranks) effectively has 300 hps to fight with before they are auto-dead. All the other guy has to do is hit you a few times and your devil will finish the job. PVP demons turn on you at only 25%... but you understand the premise.
Good conjurers can join maran, and get some nice defensive stuff. Plus, their archons will cast fast enough to make them a beefy tank.
Neutral conjurers get dick for cabal powers, and their devils + archons will be slow.
The also get screwed by random "protection from".. a conjie dam redux mainstay.
Imagine conjies as toothpicks holding up an anvil. The toothpick just needs brushed and the conjie self destructs. Only through lots and lots of +hp gear and defensive cabal powers can they really pack a punch.