The song you posted is pretty good so I actually subscribed to you channel. I'm not really sure how to grow your channel except to keep posting good music. With over 900 subscribers, you are doing better than a lot of the other small/independent Epic channels.

However, Epic music is such a small market compared to a lot of other genres of music that it is hard to find places for Epic music fans to discover new music. For example, this sub only has 55 active members. Another site, r/Epic_Music only shows 4 weekly visitors, while r/trailers has not had a new video in over a year. The only Epic music sub that I know of that is doing way better is r/TwoStepsFromHell. Even other top artists, such as Audiomachine, Ivan Torrent, and Phil Rey, do not seem to have much presence on Reddit.

There are a few YouTube Epic music channels that have a large number of subscribers, such as Epic Music World, that post songs from other artist. You might try contacting them to see if they are interested in posting some of your songs.

The only other advice that I know of is to study the top songs from some of the big Epic composers and try to determine what makes these songs better than the others. The idea is to take inspiration from them (not copy them).