OK, Spectral, here are my observations and comments for experimentation. Others may not agree and that is certainly also welcomed.
Your footwork seems a bit short and choppy for a person your size and you end your approach a significant distance from the foul line. This could be a product of your short backswing. Usually "the body follows the ball" so to speak.
I also noticed that you appear to be young and athletic at age 24, yet you are wearing a large wrist brace. Do you have any physical limitations or health problems that require the brace? If not, I think you might consider bowling without it - that will allow for more flexibility in your wrist at the time of release which could increase your rev rate and roll.
In the setup, it appears that almost all of the weight of the ball is in your bowling hand with the brace. This would cause the muscles in your bowling hand, wrist and forearm to tighten and this does not usually promote a free armswing. I have a feeling that if I grabbed your forearm during your setup I would feel tight contraction in all of your arm muscles.
I would suggest trying to move most of the ball weight to your non-bowling hand in the setup and try to relax your grip, wrist and forearm. This will set you up to have a more relaxed armswing which will most likely take a natural arc into a higher backswing. A tense wrist and forearm will also fatigue more easily over the course of a set or tournament.
Finally, it is also important to let the ball fall from the top of the backswing via gravity rather than muscle control. I don't see that in some of your videos.
PBA player Bill O'Neill has a neat tip on the Kegel Training Center website. He says that the best bowling tip he ever received was "not to pull the ball down from the top of the backswing". You can see his tip at the link below:http://www.kegeltrainingcenter.com/V2/foVideos.aspx?iKodVideo=4
Let us know if any of these suggestions are helpful. I believe that a more free armswing with a natural arc and absence of muscle control will help your game and also give your footwork a more natural and smooth approach. You obviously love the sport and want to improve your game. Posting your videos will hopefully continue the process. I would also recommend working with a coach in your area, who can observe your entire game first hand.