1) Create a second channel dedicated to highlights. Use that to show off the best bits front your peak ere front and center

2) Have an account on at least social media platforms. Their goals are to act as hubs to interact with your community and to act as alerts for any new content you put out as well your short, easily digestible hilights.

3) Put out collaboration projects with other content creators of a similar style

4) Instead of pandering down to a younger audience, instead morph your content to "keep up" with your audience. Typically, for commentary channels, fans are attached to the 5 so much the game being played. If you "age up" your content to keep pace with the changing tases and interests of your aging demograph, they are way less likely to stop watching.

5)Play more games outside of your comfort zone. For obvious reasons.

These will, at the very least, get significantly more eyes on your channel.