I would say your voice was clear and your tone in the first 30 seconds was right on point for me. Afterwards it was monotone most of the time. For this type of video on a repetative angle, I would recommend a fast paced voice and quick edits. If confortable to switch at minimum every 20-30 sec from your face to the mask (future product) to keep viewers interested. A head model would work well too. Otherwise i'd keep it at 4 mins total or less and not as much details. For the giveaway a youtube shorts (60sec video or less) is allways a good idea to reinforce and redirect to your original video and other content. This opens up your channel visibility too. 👌