Well, this is just my personal opinion and I can offer zero to "back it up". So, here goes nothing...he looks pretty upright, and it has been my observation that "upright" horses do tend to have attractive front movement, but it seems to me they are limited in the "give" or "flex" when they put their feet down vs a more angled pastern whereby putting more pressure in one spot at the "peak" pressure point, if that makes any sense. Like I said, just my way of thinking..... but if it were me, b/c of my "thinking", I would most definitely put boots on him for the "other than sand" hard ground or rock.
Anywho, he needs a trim. Boots are pricey and you want a good fit - so don't measure for the fit until he is properly trimmed.