Glad you have some time to work on your game. It can be a rewarding journey.
In analyzing your swing, I'd saw you have more of a late cast or release issue more than a power source/early cast. See the face on video. You don't really cast during the early part of transition.
During the release, in the down the line clip, you look like you tend to have an aggressive spin of the shoulders. I would work on trying to get the shoulders to not spin quite as aggressively and feel a little bit more of the back to the target idea. That combo will require the arms to work more in front of your body instead of staying behind your body.
WIth your irons, that spinning of your shoulders makes it harder for you to get your weight over your front foot. It would be adding a steep on top of a steep. Here are a couple of videos to help you understand the shoulder spin pattern.
https://www.golfsmartacademy.com/golf-instruction/spinning-shoulders-vs-core/
https://www.golfsmartacademy.com/golf-instruction/breaking-down-spinning-shoulders/
https://www.golfsmartacademy.com/golf-instruction/decoding-your-scapular-feel/
https://www.golfsmartacademy.com/golf-instruction/connecting-scapular-alignment-impact-alignment/
Happy Golfing,
Tyler
