[IshKebab]

> I can subscribe to these channels, but I can't even find them in my subscriptions. There's no overview

You can just click "subscriptions" on the left to only show videos from channels you are subscribed to, and then there's another button somewhere to show a list of your subscriptions.

> a handful of channels is a drop in the ocean of all the videos that must have been uploaded and are at least nice to watch and informative

It wasn't an exhaustive list!