I feel like the problem with gaming channels is that there are a lot of them. I'm not saying this directly to you but, anyone who creates a gaming channel nowadays would need to put a ton of effort and originality into their channels. You need to be different to stand out.
200 subs is still a good number, maybe the subs you lost were inactive?
All I can really say, as others have said already, is to push your videos out there. Promote it on youtube forums and subreddits (for youtube promotion). Just keep making videos, and have fun making them.