I would like to see a system where high channeling is actually being rewarded with higher casts regardless of the current cast and some silly RND.
My priest has 96 channeling and can cast anything from 0 to 109. landing a 90+ cast can sometimes takes a lot of tries.
and if we ignore the benediction +5 any priest can cast a 100+ if the rnd gods are in a good mood.
There should be a sliding scale of max cast level based on channeling skill. and the higher the channeling the better odds to cast an higher roll.