@JO-ski ,
Thank you so much for the update, video link, and most of all enthusiasm and openness to all our ideas.
I love your video and how you are skiing. You are definitely on the right path to improvement and harder trails.
My first observation is that you are making overall very nice round, unrushed turns. Bravo! My second observation is look farther ahead towards the valley. You vision and head are looking only a few feet ahead, at least in the first turn. This is the first thing I work on if it is an issue with my students. Sometimes that one adjustment can fix other balance and fore/aft stance issues.
Have your partner or a trusted friend play a red light green light game by standing way down the hill and have them cross poles over heard for red and open poles and arms to a V for green. You might be surprised at how far down the hill you can look and still ski in control.
I like that I am seeing snow spray primarily from the outside ski in your turns at this stage in your skiing game. Please understand that nothing is set in stone in skiing. Rather, as you progress you will learn that some things may work in one situation but not in another. Most of all nothing is static, especially stance, as we are constantly moving as we ski through our turns.
One small clarification from your earlier post. The transition, or flat ski, is not in the middle of the C but rather in between Cs. When we are learning (which is always by the way) we tend to have the ski on it's highest edge right before the transition into the new top of the C. In other words, we tend to have a high edge angle at the end of the C. That does not however mean that we have a flat ski in the middle of the C when the skis are facing straight down the hill. Ideally, you will be working towards a high edge angle at the middle of the C and the skis gradually returning to flat, for a skis length, during the transition between Cs. But first make sure you develop speed control skills, of which there are more than one.
As for tired legs, skiing, while it does not have to be tiring is after all a sport. On a green, flat run, once you become efficient, and are just skiing basic parallel turns, you should hopefully not have legs that get too tired. However, the steeper the terrain or the more dynamic your skiing, the more likely it is that your legs will tire. Most of us instructors, especially the ones over 40, do an 8 week very intensive, pre ski season ski specific fitness class, of which there are at last 7 in our town to choose from. That is in addition to our regular workouts, hikes, bikes, paddles, etc... I have students that can barely do three of four beginner runs without visible leg fatigue and borderline dangerous control issues at the end of the session as a result of tired legs, and I have some that go from 9 am to 4:25pm with a quick lunch, and are barely starting to feel the burn. Fitness is a factor, but does not need to be a limiting one. There are ways, in addition to off snow training, to minimize it.
I do not by the way think you look stiff, but again, wish to remind you and myself, that skiing is not static, nor is the stance. Often exploring what we think is a wide movement range, actually is quite limited. Video is cool that way, in that we get to reconcile what we think we are doing, (as in I think I ski like Mikaela in my mind), with what is actually happening (I look like I am barely moving - so much for being dynamic).
I hope my ramblings made a little sense.
PS You are a trouper for night skiing....brrrr
PPS I love the image you found to illustrate just leaning into the front of the boot with no other flexing happening....so funny and perfect, but maybe not for skiing unless it is going off the big jump!