25 What benefits or changes would I expect to notice if I took the shoes off my horse?
Probably nothing if you were just taking the shoes off your horse. To gain maximum benefit, your horse would need to be correctly trimmed on a regular basis and you may even need to make some changes to the way you feed/keep your horse/donkey/pony. The changes you may see will depend on the type of issues your shod horse may already have. The general things that people notice though are: a more athletic horse, better stamina, more energy, an improved work ethic, better posture, improved gaits, soundness, change in coat quality, change in muscle development, positive change in temperament, to name a few.
26 Would I be able to do a really big ride like the Great New Zealand Horse Trek or the South Island Cavalcade if my horse was barefoot?
If your horse is properly conditioned for a big ride, you have hoof boots as a back up if you need them, and the organisation that is running the event isn’t insisting on horses being shod then there should be no reason why you wouldn’t be able to ride your horse in an event like this. In fact horses that have been trimmed correctly have already been ridden at both of these events in recent years.
27 Is there anyone in my area who has changed to natural hoof care that I can contact to hear what they have to say about this method of trimming horse’s hooves?
Natural hoof care in New Zealand is now very wide spread. It is likely that there will be someone in your area you can contact. Email your request to firstname.lastname@example.org