After some testing I did ML+2 looks to be a good sweet spot. Nothing in this game says casting powers should be easy or should have a 50% chance etc..
Sooo.... here is the effect of limiting dice to ML+2:
- Almost no affect at all on level 1 powers (you really shouldn't be needing more than 3 dice)
- Sometimes a bit of a drag on level 2 powers (you'll get em off about 2/3 of the time throwing 4 dice if you're a level 2 psyker)
- Makes casting level 3 powers quite difficult (you'll get em off half the time if you have a ml3 psyker, and much less than that if you don't have a ml3 psyker).
Is this what you are going for? What's the reasoning? Are there specific level 3 powers which you think are more of a problem than casting mutliple level 1 and level 2 powers? What problems do those powers cause in the absence of this mastery-level based dice limit per cast?