Theses Youtube channels have low subscriber counts but great content.
About a couple and there dog living full time in a large RV. They created a new channel recently so the subscriber count is low. Their channel has a loyal fan base though and Chris and G have great personalities. Currently they are in Alaska after driving up through Canada. The videos are very scenic and informative. If you like travel logs their channel is spot on. Lately they have been uploading frequently but I know they are working on other projects.
A outdoor survival and wilderness guide channel. The host is Kenton Whitman who has created some intense survival videos. Also he has some videos on personal well being and life lessons. If you are a nature enthusiast this channel covers a lot of ground. TV shows like Survivor Man and Naked and Afraid come to mind when watching. There isn't a schedule for uploads unfortunately.
Let me know if you heard of them before or comment some lesser known channels you subscribe to. I have some more for a future post to share. Hope you enjoy these!