I had written a long response to this but my computer crashed, so here is a shorter version
I run into the same issue regarding it being hard to get film of myself as I also mostly ride solo, but during lessons, always ask your instructor to film you & you can review the film with them on the chair lift! Can also ask someone cool on the chairlift if they wouldn't mind filming a lap for you. Most people are happy to help someone wanting to improve.
Stance width / angles:
For stance width - if your board is the right size for you (weight-wise), just use reference stance. This is usually equal to slightly more than shoulder width apart type athletic stance that allows you to squat and stand up easily (usually the same length as your forearm). What is your weight, board length, and stance width?
For binding angles - probably easiest to start with a symmetrical duck (+9/-9, +12/-12, or +15/-15) depending on what feels comfortable for you. That way you can also practice what you are doing switch as well.
Or can try a slightly asymmetrical duck (+18/-9 for example) or even positive/positive angles... there is really no right answer, depends on what feels comfortable for you. But I think symmetrical duck is best while learning in the beginning so can learn switch in the beginning.
Counter-rotation:
For a regular rider, your front (left) shoulder should go right when turning onto toes and go left when turning onto heels. You describe front shoulder going right when going onto heels, so that is the definition of counter rotation. You can be well aligned during the transverse but still counter-rotate during your turns. Best way to tell is just to film it. Drill would be riding with your hands on your hips and concentrate on where your front shoulder goes during each turn. If the front shoulder is going in the same direction as the turn, then you are doing it right.
Weight Distribution:
To be honest, probably best to just try to keep your weight centered on the board to start. You can do small hops while riding and trying to stay & land on your edge to start (hopping will force your weight to be centered). More important for carving is engaging the edge by using your lower joints (especially ankles and knees) and sounds like you are still practicing that.
The weight shifting (more weight on front foot at the start when turning... and then shifting weight back to keep the edge locked down for your back foot while you are finishing the turn) is more advanced add-on skill that is more useful when you figure out how to use your ankles. Weight should be slightly forward on the front foot at the start of the turn because you can turn easier with more weight in front. Weight goes back as it helps lock down edge and prevent the back foot from skidding (however, if your ankles aren't locking in the edge, you will still skid). To practice the weight shifting, you can try to carve uphill after a traverse - you need to move your weight slightly back onto your back foot to go uphill on a carve.
Body positioning:
Try the body positioning of toes and heels in the carving video above from snowboard addiction while strapped in but on flat ground (maybe even at home on the carpet). Do it next to something you can hold onto for balance. You can even setup your phone to take a video/photos of you practicing, and you can compare your body position to the videos. It is a lot easier to tell what you are doing wrong when you can see it yourself. You can even pretend to make a turn and see where your shoulders go. You can post that type of video / picture to get feedback on your body position as well.
Skidded turns vs Carved turns:
Skidded turns is a perfectly viable way to ride (for example, mogul riding or riding on ice is mostly skidded turns). Carved turns require a lot of your body position and technique to be really on point, so that's why it is good practice. Focus on good skidded turns with the right body position and technique first prior to worrying about carved turns. When you have the right body position and technique, trying carved turns becomes a lot easier. When practicing carving, do it on a green slope - you will pick up too much speed when learning to do it on steep slopes and you will need to skid to slow down.
Hope this is helpful & good luck!