The thing that sticks out in the video is how uneven your edge angle is toeside vs. heelside.
In the video you are extended when changing edges then sitting down in your heelside. But, when you sit down through your turn it doesn't increase your edge angle or do much of anything. Also, if you try to push your hips into the turn more, you'll typically fall to the inside of your turn. Staying taller and tipping/leaning into the heelside turn with your whole body will help you generate more edge angle as others have said. But as snowolf suggested and explained perfectly, I would have you shift to down unweighting, ie compressing at edge changes(I know you said you have down unweightin, well, down, but if you are getting more spring up unweighting, then it needs work).
The trick to a really solid heelside carve in soft boots and ducked stance is to angulate such that your hips are BELOW your knees during your turn.
I think getting compressed at your transition and then extending through the turn(ie down unweighting) would improve your heelside dramatically. This way you can be fully compressed(to give you an idea, if I am really banging aggressive carves, I can feel my knees hitting my stomach/chest while changing edges and therefor they are above my hips). Being that compressed allows you to open your lower body and extend while keeping your hips low and moving to the inside of the turn which will create edge angle and even out your turns.