I ride the Flag 161, best deck ever.....for me. I love the thing. For a one board guy(me) its perfect. Don't let the hype fool ya, its not crazy stiff and hard to ride.
I have done it all with mine, teaching days on the bunny hill to serious backcountry lines.
I would love to add a Mtn twin to the mix, for a playboard, but I don't think I could have one as my everyday all mtn board. Too soft and "freestyle" for that.
Don't get me wrong, it would work for you, just from your description, it seems you may be wanting a bit more from it than it wants to give.