How would I know the difference between tongue sensitive and hard mouth?
He will ride with his mouth wide open and his tongue hanging out...? and he's really head flingy. He also gets really choppy but I don't have an english saddle that's wide enough for him (the girls that come out do have one). I used my western work saddle on him the other day and I think it may have been too narrow. He is built like a draft, even though he's only about 14.2 and a half, he's HUGE in the barrel....
As far as for the saddle, get someone that can fit saddles to tell you if your saddle fits. If you are at all unsure if the saddle is fitting well - then don't ride him in it! You are just creating more and more problems by riding the horse in ill fitting tack.