You might find that that Arab IS your dream horse and you just don't know it yet.
That's what happened to me.
I wasn't really prepared, at all, to own a horse but an older friend of mine had found "my horse" and offered to pay her expenses until I could myself (not a great initial choice but we're past that now).
Anyway, I had adored Arabs when I was a little girl (what little girl doesn't?) but had moved on to wanting either an appendix or an Appy for my first horse.
I wanted my horse to be young enough to have lots of years left but old enough to be really broke (I was thinking 15ish, tops), super broke, safe, you know the deal.
I met "my" mare and something about her "did it" for me. She was a gray Arab mare, 23 years old, barely green broke, had been retired for 12 years after a serious accident with a rider...basically everything a new horse owner should NOT get for a first horse.
But I took her home and now, 4.5 years later, I cannot even describe to you in words how much she means to me. She's nearly 28 now and my best friend.
It took a few years to get her trained but now she's trained pretty much exactly how I want. There are a few things she can't/doesn't do, but in everything she tries her heart out for me.
This last spring, she went mostly blind and I thought that was going to end us. But it didn't! She's playing to stay and she's doing a great job. Then, in the fall, she partially tore a suspensory in her leg and again, I thought we were done. But NO! She's now sound again and we're going to try riding again next May.
I remember though that during the first year or so of "us", I was pretty sure one of us was going to be killed by the other. She was basically nuts and I had nowhere near the skill level needed to deal with her. Now she's so steady and reliable, I can't even imagine feeling that way.
Sure, she does have "Sass Master" days where she tries my patience something awful BUT then I look in her eyes and see the glint that says she's trying to get me to sass her back...those are things my heart holds dear.
ANYWAY, bottom line: like LadyDreamer said, don't limit your dreams. You never know what you might become with this mare.
I certainly had no idea of how much being an "us" on that much of a soul level would change me!