I think he's definitely got welsh in him. I've never seen a connemara in australia (not to say they're not here, only that i've never seen one!!) so I can't really say anything about that. As for australian pony, most of the time they're the finer types, but my pure bred is quite stocky with larger bones and features so you may even have some australian pony in there somewhere. That could also explain his dominant (or "pig headedness" haha) mood as my pony and quite a few other australian ponies I know have the same type of mood!! Does he have any brands...?