Michael, interesting format. Always nice to hear someone sharing their passion. There's lots that could be said, but generally I think its important to start with the core of what you're doing - sports commentary.
Commentary is a difficult area to engage an audience with, as most sportscasters, pundits and commentators have earned their place and viewers and listeners believe they have credibility. You should ask yourself, why do I deserve someone to listen to me rather than someone else? Why am I credible? And I'm afraid, because you care or have an opinion just won't cut it.
Think about evidencing your opinions, and how sportscasters and pundits evidence their opinions. They use stats, they refer to previous games, they refer to performance on and off the field. That's also a useful way you can get more footage: including screenshots or recording your screen viewing stat websites, etc. would give you something to refer to.
Thinking more generally about gaining a bigger audience: what is it you want to comment on and how popular is that as a subject? The more popular a debate, a team or a player, the more people will search for that and find your video.
A small point, but always try and use images and footage which is 16:9 to fill the whole screen, and as soon as you feel comfortable recording your face - even picture-in-picture - it will help you connect with your audience and gain further credibility.
Good luck, thanks for posting.
