At the very least, everyone should use RTH once in a while to make sure that the behavior is what you expect/hope it will be if you should lose the link and have it start RTH automatically. It’s just prudent to do that.
What regulation would RTH violate?
It is actually referred to in several Part 107 test questions as a preprogrammed Lost Link procedure.
In our Certificate of Waiver and Authorization it is specifically mentioned "Prior to takeoff, the sUAS must...
I am not sure what all the hate is about with RTH. I used it the other day when mapping. Out of 6 flights, I used it 5 times. It takes some of the workload off at times. As with any automated function, you should read the user manual and...
Since the option to record embed into the video recorded on the drone isn't available, that would be the only way to record audio, which would have to be synced and added to the drone video during editing.