dry cider would help with the sweetness, though probably not with the relative lack of apple compared to your honey character.
also, we really don't know why it stopped. I still haven't seen any pH posted, or any mention of nutrients added during this fermentation. I don't pretend to know alcohol tolerance for WLP070, but I've never had 71B stop that early which was one of the yeasts pitched. (granted they weren't exactly pitched into a friendly environment)
It's a bit late now that 3 yeasts have been tried and the mead racked away from them, so, if it were up to me I'd probably chock this one up to the learning process and decide to do a few different things with it. Store a gallon in a jug - it is amazing how time can mellow what initially seemed like excessive sweetness in a well-aged sweet mead. Take another couple gallons, water the alcohol down with some apple juice, adjust pH if necessary, add some nutrients, and pitch some 71B. Mix another gallon with dry cider to taste. etc, etc.