I am under EBMAS, so, probably not the same lineage, but from that point of view I can offer a few suggestions.
before that though, I can tell just by watching your form, your conscious of things your trying to change and putting a lot of effort and heart into it, I feel like that is half the battle, props to you!
like stated above the stance is a bit too wide, should be shoulder width in line with the heels, although if your really tall and skinny like me, you may want to open the stance just a tiny up more than that. I would put your toes at a 60 degree angle inwards.
In my lineage, the opening double tan to gan sau starts at the chest level, than goes down in a double chopping motion not locked out, but close to it, and than back up to chest. your qwan sau looks pretty decent for not having a live sifu. when you bring your elbows back, in my lineage, you want them pulled behind your nipples, at the height, elbows in line with your shoulders, and we think of it as an elbow strike. it's a good stretch! the fist in your punch should be vertical. the punch starts from your solar plexus area, the elbow follows along the centerline, make sure your stretching to do that! our punch contains many movements, our spine straightens, our fist face is pulled back by our wrist, to create the one inch punch. our shoulder gets pulled back at the end of the punch, all of this is timed to let the energy pass through whatever we happen to be punching. after you punch, from a vertical fist, you open your fingers than turn your palm so it's facing up, than you pull the fingers back as far as you can, trying to touch our forearm, while holding that position we than rotate our hand so the palm would be facing down. while your fingers are still stretching to touch your forearm, you will make a fist, it will point straight down, this is another really good stretch. it than pops up, so you look like your punching like a boxer more or a less, aside from your elbow being aligned to the centerline, than we will execute the one inch punch motion by moving the wrist towards out center, or if it was vertical up. than we turn our entire arm upside down and pull back for an elbow strike. I would just focus on trying to perfect these movements first, before you move on the next. The kind of patience and diligence you will need can be tested here. If you can work on the same 2-5 motions over and over for hours your on the right track.
The thing about all of this is that, when you do eventually find a teacher, your going to have to unlearn EVERYTHING you have learned, and that is really going to set you back, everything you will have done up until that point will have been wasted time, and in fact will make it much harder for you to learn properly your new lineage.
In any event, I can see the hard work your putting in, so you have my respect and best wishes, best of luck to you!
