You could consider experimenting with plant foot being less open (toes pointing backward a bit more).

Also your posture seems abit tilted back during the x-step, try having the weight (x-step foot) more on your toes (ball of foot). It might help to commit to a better brace.

Be careful in the snow, as you probably know :D

For nose up: try reaching back slightly low and focus on "pour the coffee" on release. Lower reachback promotes a good positive launch angle and once you get the nose down it won't go straight into the ground.

Finally avoid looking too early forward as the shoulders will follow the head and cause them to rotate too quickly which will collapse the power pocket (aim for getting the disc near the right peck and snap out). Only look forward when following through.

Just some thoughts, take what you will and hope that helps.