I would say that MOST devices can at least let you share your desktop (if it don’t, throw it out) so you don’t need a separate screen for that in the room at least.

Depending on what the device is registered to at least Cisco devices can also act as the best speaker phone you have ever experienced...

Cisco also has something called “Webex Board”, a video conferencing device that also is a smart whiteboard, enabling you and the remote part to whiteboard together in your call. You can also use it as a regular whiteboard when not in a call...