It's been a mystery to me why they focus so much on mounting the iPhone to the MacBook. There are a million better ways to position your phone as a camera. The quality is very good, but the connection/disconnect/pause is a little buggy.
It's also interesting that they didn't extend the Continuity Camera to iPads. Sure - who would bother, but then again, why not just include iPads in the mix?
Similarly, I wish Universal Control worked with iPhone. It's very handy to just swipe over with my mouse to my iPad to click on something - it would be equally handy to do it to my iPhone sitting here on its charging stand.
Interestingly when I use my BT keyboard and mouse paired to my iPad, Universal Control seems to work in the reverse where I can originate on the iPad with paired devices, and move them to the MacBook. Have to experiment more with this to confirm, but it doesn't seem to matter which device your mouse/keyboard are connected to which is cool and perhaps an obvious idea, but not all these sharing mechanisms are bidirectional.
With Universal Control and Continuity Camera, it feels like we're in the very early days of a perfectly seamless sharing experience across Apple devices - they're 10 years (at least) ahead of Android/Windows in this space.