Great pictures, Danee! I hadn't even seen this intire page yet...
I love your riding at liberty with your brown one. The riding looks lovely, very strong and relaxed at the same time.
By the way, I just read that a tailstrap (I don't know how your call them in English, but the strap that you put from the saddle, under the tail and back again in order to keep the saddle from sliding forwards), will cause backpain to a lot of horses. It's because their tail is a quite vulnerable extension of the spine, and isn't built on being pulled up and backwards by the saddle - and pulling the tail up is contra-productive to training collection again. I just wanted to let you know, so that maybe you can find another solution?