Kevinshorses, I don't see why you're so dead set against horses going bare...
To the OP, going bare should not be done if you don't want to do your part. There may be a need for boots and foam pads to help your horse adjust to being without metal shoes, which requires labor on your part. It's not an instant magical fix to lameness, either. It's a process that takes time and good trims along with a good diet and exercise plan, which ANY horses, shod or not would benefit from.
Metal shoes do offer comfort for horses that are used to them, and you can make a horse seem sound in them (metal shoes dampen sensation in the hoof), and as an owner, there's little you actually have to do with the shoes, beside making sure they are still on and in place between farrier visits.
Barefoot trims require regular trims, just as often, maybe more so, than shoes, as the hoof grows faster without metal shoes in most horses (so that should alleviate fear of wearing faster than they grow). I've never seen a horse suffer from true wear that took them too short. I've seen chunks break off too short, from BEING OVERGROWN and poorly trimmed, though. I'm not saying a hoof never needs protection to do the unnatural tasks we ask of our horses..that is why there are so many hoof boots now. Boots absorb more shock, protect the foot, and yet allow it to fuction more normally for the horse, and metal shoes simply can't do that. We have the technology that is better than metal, that is what barefoot is about-to let the hoof itself function as closely to normal as we can, to promote soundness and usablity in the horse. Metal shoes don't offer true soundness-if your horse can't function without metal shoes, he isn't sound. Personally, I"ve fixed horses barefoot that were supposed to be put down when metal shoes couldn't fix them anymore.
Yes, even club feet can go bare, but your hoof care provider must know how to trim it and not fight it and exaccerbate the problem. If you do your research and find someone qualitfied, it will be a satisfying experience. I do not condone just trimming your own horse without a lot of research, guidance and experience, as that is a recipie for disaster, that applies to healthy feet, as well as pathological.
Overall, getting out of metal shoes could make the biggest impact on your horses performance and health, but keep in mind that holes in the rest of your horse keeping will show up more easily-thrush is more apt to cause lameness, if you never clean the stall, but the incidence may be less without shoes, too.
I don't agree that going bare is any more expensive than having your horse shod, even with boots and pads being purchased. It may be less costly, or about the same averaged out. Don't decide your horses hoof care solely on cost, do what you think is right, and using the professionals available to you that are most qualified, regardless of what style you pick.