Pasterns - The pastern should be at a 45-degree angle (example A; example B shows a too-sloping pastern; example C shows a too-upright pastern). Its length should be proportionate; too long a pastern could indicate weakness and tendon strain, while if too short it may absorb too much concussion, thus stressing the bone structure.
Do you trot her much? My mare when she was being difficult would have a real choppy trot (and she was one that could trot faster than Prez can lope)
She just needed to be pushed a little and she was smooth enough to sit her trot for miles. We actually did an 8 mile competitive ride at an extended trot the whole way. Well except for her walking across the bridge and jumping the tire and water obstacles :)