I'm thinking that I'd rather not have to roll for NPC spells and to just go with average success rate and spell points..hence, not having to roll or deal with spell points in this regards. Any suggestions on how to reduce the GMs burden when it comes to NPC spellcasters?

jh

I just use NPC spells like normal action cards - no power needed.

It is so much easier to handle. I just observe how well the group is doing and act accordingly.

I keep it challenging but do not overwhelm them - unless the NPC is considered a "boss mob".

I do that too. My limit is to use every spell once before doing again the same spell.

I often use a d6 if I want to make things easier/faster for me. 1 is bad for the players while 6 is good. I usually avoid doing combat by the book because it gets boring really fast. The time spent rolling or declaring what actions you use just eats up too much time in comparison to actual play. What also helps is just defaulting the actions which means some street thug will have low results while some trained soldier will trigger medium effects. This only works if your players do not demand that you roll everything as it is written in the book.

Example:

Thug has 3 str and 1 challenge die. Therefore he gets 3 successes and 2 misses. Left is 1 therefore he hits with str+weapon. This is the basic idea which can be translated to any other unit or action. Regarding power and caster they just have their willpower level of power all the time and if they cast something bigger they get another challenge die for quickcast (all without actually declaring or rolling it) and therefore get another 2 misses. If it would be interesting from an fluff/story perspective I grant them a sigmars comet or chaos star to influence the scene in a cinematic manner.

There are a couple of NPCs in various adventures that say they "have enough power to cast one spell per turn". Krasskulk from TEW, for certain, but I don't think he was the only one.

Since there's rarely anything the PCs can do to disrupt the NPCs ability to channel or curry, it shouldn't be very problematic to skip the dice and just assume the NPC automatically returns to Equilibrium every turn. For fairness, you should probably a purple die (as if quick casting) any time they cast on consecutive turns or use a spell that takes power beyond their Equilibrium.