Your comments

Requires implementation of MTP (Media Transfer Protocol). You're basically asking us to re-create another $40 software product for free. We've just tested MTP Drive and it works fine with TeraCopy.

We'll add an option for the second progress bar, what information is most important for you?

It's out of scope, did you try MTP Drive or similar software?

Just repeat the copy process with TeraCopy. Using TeraCopy option to bypass Windows write cache in version 3.3 is a better way to avoid this problem: