OP, I think you’ve absolutely made the right choice sticking with the new barn. Here are some experiences I have personally had (keep in mind that every trainer is different).
I was VERY fortunate and had the opportunity to own three horses in high school. Yes, I was able to have a very successful show career and do the Juniors, win some big medal classes, etc.
But, I can honestly say that the time I spent before I got said horses, riding anything my trainer had that I was capable of doing anything on, was where I got the best experience. I was pretty small so I rode everything from ponies to jumpers. Did I jump these horses 3’6"? Absolutely not. Some of them I just practiced my flat work on. But it made me capable and comfortable when I got my first hunter. In fact, after owning my same horses for a few years, I definitely regressed in my overall horsemanship, simply because I got used to the simplicity of riding a horse that I knew.
By the way, I’m in no way saying that a lease or owning a horse is a bad thing. I’m just saying that you definitely don’t need to worry about yourself not progressing as a rider without a consistent horse. I also completely understand your concerns about IEA and IHSA. No criticism there. Only you know what you are comfortable with. But, your new barn will hopefully provide you with some useful horses to ride that your trainer knows, which is a totally different experience than drawing a random horse.
Okay, so next chapter of my riding career. Went off to college, sold my horses to help pay for school, and went to a primarily jumper barn. Because I was a hunter rider, the trainer didn’t feel comfortable letting me jump anything besides the lesson horses. At this point, I found that I really had to increase my riding frequency to get the same value out of my rides. I was able to focus on basics (strength, eye, position, etc) even though the height was low. I was no longer able to show much, which was hard for me because shows are so much fun!
I eventually found a different barn that was predominantly hunters with a well known trainer and very nice horses. This ended up being a great situation. The trainer knew I was in school and didn’t have a horse, but if I was willing to ride, she did everything she could to put me in the saddle (even if it was only on the 17 y/o rusty stirrups horse). I would go to shows just to watch and enjoy the atmosphere and help out, and more often than not she would let me hack some horses or warm them up before their owners got there. She generally paid my hotel fees in return. I gained so much great experience from her, and I never leased a horse at her barn.
My hope for you is that you develop a trusting relationship with your trainer, show your willingness to learn and ride, and can accumulate similar positive and inexpensive experiences. Best of luck to you!
BTW, I am not at all harping on your taste for nice riding stuff, this sport is filled with people with expensive taste, that’s why all of those companies thrive and can charge what they do. But, just know that I won some very big classes wearing a generic Charles Owen, Ariat boots (not Monaco’s), and a Dover circuit saddle (I just now got a custom CWD because my horse has no withers and 3 used saddles in a row were killing her back). Also, these things weren’t the hottest trends, but they were still far from inexpensive. Once again, have at it if you want nice stuff, but don’t ever let anyone make you feel like it is a requirement to win or fit in. A nicely and neatly turned out classy rider is priceless.
