#1 and #3 jumped to mind (i personally apply number 2 to number 1).
To comment on number 3, many people learn differently. A good trainer knows this, and is good at individualizing his teachings for his pupil imo.
What i personally cant stand, is trainers trying to mold their fighters into their own fighting style, taking them conpletely out of their element and strengths. Imo, a good trainer understands his fighters style, and works from there, developing their strengths and weaknesses. Im guessing some might disagree with this?