I have no channel or a youtube account, but have spent many many many hours watching youtube videos on modelling so I'll give you my two cents worth on what does and doesn't appeal to me the viewer looking for answers.
My tip on the music is, you don't need it. It is a distraction and the music on the scorpion build part 1 is sleep inducing. You are quite adept at being able to continue talking while you work and what you say is what is important for people to hear. You might want to include what products you are using the first time you use them. What type and brand of glue, what you are sanding with, cutting with etc. I know I needed that info greatly when I started back at this hobby and I think your videos are great for beginner folks trying to find answers on how to do builds. Including that info would kick them up a notch. No need to show all that sanding of small parts, maybe just one or two then cut to next step.
What I find spot on is your Rubic's cube intro is great and a quick attention getter so you want to hold that attention throughout the video and keep it at that level. I like the fact you don't ramble for two or three minutes at the start, you just get on with it like a person should, and if you shorten the sanding part like I mentioned, it will make it even more appealing. Overall you are off to a good start. I can't tell you how many videos I've stopped after someone starts off rambling about crap that matters not. Ugh that is irritating. I hope you can use some of these tips to help you in your endeavor.
On another note, what if Bob is my Mother's Brother and not my Father's? Never mind, it doesn't really matter, either what Bob's your Uncle, and there you have it from a viewers perspective.