Don't forget the forward speed. I also find that the more I do loops, I typically don't have any negative pitch anymore for the high speed loops. I'm at 0, if not +1 - +2 Degrees, most of the time in loops. You can use your cyclic to control the height of the loop. Really high round loops, pull back slowly on the cyclic while maintaining positive pitch, slowly ease off the pitch as you get around the inverted point, and before you get back vertical start putting the positive back in. That's how I do em most of the time.