I watched a bit of your latest video, and I quickly noticed a big problem :/
You mumble, a lot, a lot a lot a lot. I couldn't understand entire sentences from you. If you're a natural mumbler, that's something you'll have to put effort into making sure you aren't doing. That really needs to be solved before the other problems...
Now on to other problems... You are very monotone. I had a chemistry teacher once who was very monotone, and he was actually a really funny guy, but I couldn't pay attention in class at all just because of his voice. When someone is monotone, whether or not it's just how you naturally and comfortably speak, it makes you sound very disinterested in whatever you're doing. I love art, and had another teacher, an art teacher, who nearly turned me off art classes for my entire high school career because of her voice. Another problem is you're getting too close to your mic, that's where the popping comes from, and why we can hear you breath.
I hope this helped, and that I wasn't too harsh.