She's gorgeous!! I have a soft spot for "older" mares, so I love her!
I don't have any personal experience with Friesians, but, from being on this forum for a long time, I've always heard that they do not make ideal dressage mounts. I've always heard that they are popular for dressage due to their flashy movement, but that it's not easy to get them to do correct dressage.
They were originally bred to be light draft carriage horses, and that doesn't always translate well undersaddle.
My main concern is that you will end up running into many of the same problems you're having with Sydney.
With this mare's age, it's only going to get harder for her to move "correctly." Also, at her age, selling her on -if she ended up not working out- is going to get harder and harder every year.
My first horse that I owned was sold to me as being 21 - turned out she was 24. I owned her for 5 years before she passed away at the age of 29. She was the best thing. I had lots of extravagant plans of things the two of us were going to do...but she ended up not being up for most of them. It was ok though - she taught me a lot more about who I am, who I should be, how to enjoy life, etc, than I probably ever would have learned if all my competitive goals had worked out.
I'm definitely pro-older horses, but they have a shorter "let's do all these activities and then let's go to ten shows!" tolerance than a young horse might. You kind of have to go at their pace and understand that competition may or may not be in the cards.
Are you ok with having a big pet/trail ride horse in a couple years, for longer than you had a dressage horse?
I'm all for older/senior horses and I feel like everyone should own at least one of them. When you're new to the ownership gambit, it's sure nice to have an experienced horse that doesn't get overly worried about details!
Fabio - 13 year old Arabian/Lipizzan gelding
Rest peacefully, Lacey.