You spent 2 years trying to put your horse in "an outline", which is certainly worse than riding her in a bit.
I have noticed a correlation on this forum, among people who ride with a lot of contact, thinking bits are cruel. Maybe they need to consider it is cruel because they are riding with a lot of contact, not that the bit itself is the problem.
I will probably get flamed for this, but I see people on this forum, almost constantly, preaching snaffles are the only mild bit and if your horse doesn't respond well in a snaffle he needs more training (or like this poster, don't use a bit at all because they are all cruel!). And these are frequently people who ride English style with contact, trying to put the horse in a frame. I guess because they think it looks pretty (I admit it does) and they are somehow doing it for the benefit of the horse "working correctly" (which I don't think has actually been proven.....horses don't travel collected in a natural state very often, so I would argue that the horse is not designed to travel that way). Then, if the horse gapes it mouth or flings it's head, they use nosebands and martingales to try to quiet the horse's protests.
Maybe, just maybe, if they didn't ride in contact to begin with, they could actually use a curb bit and have finesse with their horse. No pulling, no nosebands and martingales. Just a feather soft horse. Or course the bit doesn't do the training for you, but what I am saying is that you can achieve a beautiful, light horse with a curb bit. And most of the time your horse is traveling with a loose rein with no contact at all. How beautiful is that?
So yes, please, use what works. If your horse rides in a halter, great, I'm all for it! That's fantastic. But, I have had this casual observation that the people bashing bits are either beginners who don't know any better or people who are too heavy on their horse's mouths and ride with tons of contact and then wonder why their horse is unhappy. Instead of looking at themselves, they say "it must be the cruel bit!"
I don't think I know a single experienced horseman who thinks bits are cruel. Maybe there is one out there, but I have never met one.