I just watched the video. Being honest, the intention and aiming is good, however the motorcyle reference within the video is the windscreen, and that could be a good reference but the distortion is is pretty bad based on the road lines.
The mount location seems good being stable, just not sure if it is possible, even with zoom to remove the distortion areas. Also, some distortion on the edges may happen from the camera itself naturally. Thing is, your video has a large percentage of the image looking through the windscreen.
you mentioned the mount was onto a Ram ball which is on the handlebar. Can this mount be safely moved forward or further outboard?
In regards to image quality and degradation, finding a good converter is important. I think you mentioned going from AVI to MP4. Not uncommon whether done automatically or by user selection. You may also want to experiment and see if conversion before or after importing into you editing program helps. Also, if there are sound events that key to visual, ensure the conversionretains the timing. As an example when a ball bounces, is the sound of the impact aligned with the ball hitting the ground?
I am not sure what software you are using, even the best is always degraded by Youtube for uploading. Keep that in mind if you play the same video on the same monitor with a before and after upload comparison.
Keep at it, once you find the true best mount location, it will capture incredible video that is easy to watch in 5 minute max duration.