MS surface hub for the meeting room (can be wheeled out if on a TV stand) and MS Skype for business is the optimal. The surface hubs aren’t cheap though.
With the greatest respect you’re trying to make an old solution, that was fairly crap, work better with new, and very expensive hardware.
If you *really* want to gather everyone around a table to watch someone on a big screen there is better kit for the job, but it’s a bit old school to say the least.
Most places don’t bother with video now – it really don’t add much, better to share a screen to display what you’re talking about rather than your winning smile, but some people still like it.
It’s better to allow people to stay at their desk, use a headset (partly because it’s easier to hear and partly because it saves your neighbour from having to hear it all) you can add a webcam if you really want to but – you can have up to 16 people on a video call anywhere with a web connection, or 250 on an audio call (more if you pay) obviously a 250 person audio call is actually a presentation rather than a meeting so you’ll want to mute the bulk of people unless they need to speak.
Headsets are cheap and easy to use, Skype for business works very well and if you’ve got 365 it’s part of the package.
Use it for a while and my pie in the sky vision of the future where office monkeys like me can all work from home seems not only doable, but better than what we have now.