Hello,
I thought to collect some useful resources specifically about faces here.
First, since you were talking about things like glasses, goggles etc. there's the chibi stickers example project that showcases several of them:
The video at the bottom shows the creation of the Spineboy skin, but the rest still applies!
The trick is to assign exactly the same weight to places you want to touch.
Pretty much as in this video on the arms to get them to be connected.
You can see hair strands floating in front of the face while being separated also in this video:
Both projects showcase how to rig faces so that they have volume but can also open and close the eyes or move other parts, so I hope they can help!
If you have other questions, please also post visual examples, as that makes it easier to give tailored answers.