In general this looks pretty good. You’re using the Andy Wood style of this, i.e. lightly supinated, “902” wrist motion. Speed is the test for these things. If you feel like you’re hitting any kind of wall below about 140bpm sixteenth notes for this kind of line — or becoming unnecessarily tired — that could be an indication something isn’t right.
I was going to say it’s a little hard to hear with the guitar unplugged but you should still be able to get pretty significant volume out of this even unplugged on an electric. If fast is one litmus test, then loud is another, at least when it comes to bluegrass. So if you feel you can’t get loud enough while playing fast, and without quickly becoming tired, that’s another thing that might indiciate something is up. Either that, or plug in for the next demo.
When I use Andy’s approach I like to stay a little on the “ulnar” side of the wrist’s range of motion. In other words, I want my hand / arm orientation when I play the lowest note in the pattern to be straight. I don’t want to feel like it’s bending toward the thumb. When I do that, I sometimes feel like I have to involve other joints or maybe can’t go as fast. Playing three strings requires a fair range of motion and I like to make sure it’s centered where it’s comfortable, which means, again, a little off-center as far as the forearm is concerned.
Also, try not think of this is a form you just use for arpeggio picking, because it’s really a form for playing anything with the wrist, especially if it’s complicated. So practicing other patterns like scale things or oven blues things will help make it more obvious if the form is really working.
Got some work to do around the house at the moment…