...So I guess a lot of it comes down to us and how much time we spend of getting a good relationship with our horse, how much trust we put in them. To have full trust you have to give it, with 500kgs of spooky horse flesh that can be hard, but we expect them to trust us and go past all sorts of things that go against their instincts...
...I think it doesn't matter what you ride in , in the end its about "does your horse trust you" and if he does than you have the world :)
Well, I've got 4+ years sunk into Mia. I've been with her when she was sick, walked her for uncounted hours on a lead line, ridden her uncounted hundreds of times, spent a couple thousand dollars having a professional trainer work with her...
I expect her to trust me because I've earned it. Not only am I smarter than she is, I feed her and water her daily and couldn't estimate the hours I've spent with her. But the trainer warned me that Mia would always be an intense horse, very alert and maybe a bit too much imagination. I'd have sold her to a better rider by now, except better riders don't want to buy PITA horses. She is improving, slowly.
It does matter what you ride in. I use an Aussie-style saddle because I'd have hit the ground a number of times without one, and I already have an almost 4 year old back injury from the one time I came off of Mia. Tack matters, which is why we spend money on it. There is a reason why most people use reins and stirrups. Not every horse needs reins and stirrups, but darn near all will need them at some point in their life, and most need them most of their lives.
Not all horses need bits. My Appy gelding can be ridden without one, but he seems to relax more WITH one. He'll obey well either way. My mare is a lot more intense. When she starts to worry, she wants me to play with the reins and tell her I'm there. 90% of the time, I could trail ride with her in a sidepull halter. It the other 10% that becomes dangerous for her as well as for me - yet I am 10 times closer to her than to my Appy gelding.
Different horses. Different personalities. Different needs. One of the things that 4 years of living with Mia has taught me is that training & personality counts for more than 'relationship'. We've GOT relationship! It is training that still has holes, and to a certain extent, it is her personality.