Edited to leave only the parts I'm responding to.
Originally Posted by WildestDandelion View Post
I will ride him out, and he does fine, but once we turn back around (doing laps around the property, to build up muscles) he gets antsy, wants to trot towards the barn (where he knows he will be untacked etc).
You are training your horse right: you show him how to get release, and he's giving you the right answer. It's not a problem - he's just being a horse. So you need to rework his expectations. Do several laps so he knows returning to the barn doesn't mean the ride is over. Return to the indoor arena so he knows returning to the barn doesn't mean the ride is over. Take off the bridle but not the saddle and let him stew for 15 mins in the cross ties. Dismount and remount often - not excessively, especially if you have to mount from the ground, but often enough to shatter his mental image of what "end of the ride" looks like. Keep him mentally off-balance. Do end the ride as soon as he behaves in a manner that is pleasing to you, so he'll try more of that.
He's also tried to run me into low hanging branches.
You and me both. They always find those. There may be low-hanging thorny shrubs hanging into the trail, and you can bet my horse will ride my legs into those, too. I once got one of those climbing thorny things in the face at the canter. Walking next to a fence (say outside a pasture), I always have to be mindful about how close my knees are getting to the fence posts. The evil little monsters!!!
You are right, though. What you describe doesn't sound barn sour, it sounds like anticipation. You simply trained him to anticipate and look forward to comfort: saddle off, face stuffed. Make is life a little less predictable, and go reward him for the things he does well. I don't think you need to "correct" him or something like that, because he doesn't sound mean. He's simply working the script of what has been working for him, and if it doesn't, he goes to trial-and-error (like crow-hopping, as you mentioned) to make it work regardless. I think the easiest would be to turn the current signals of "Work is over" into "There is a lot more work ahead, by friend, sorry!"