I would consider getting a hold of a bunch of cameras setting up on tripods before.... no one like choppy shaky video. (even with youtube, while vastly better than zoom you cant be sure everyones internet/ comouters / tiny phone screens will produce a nice image)
Even if just 2 you can move the other around while staying with the first one. Multiple camera operators would def be a plus. are they hiring a pro videographer(s) anyway?
He would more or less be filming the entire time... if you can hook up broadcast equipment to his cameras and have someone outside with a livestream control board that would not take up a slot...
With a pro system you would be able to use prepared graphic overlays and easily switch between cameras.
Make sure you have legit fast internet (maybe ethernet cables) to connect. Dont rely on ur phone hotspot.
Make sure to have a good mike for the chuppah and try to hook up to the band or fixed mike placement near a monitor.
Keep in mind many parts will be boring to watch and you may want to have prepared videos to play (i.e. shmorg, meal,) (i.e. chossons friends/ family with a personal message or pulling people over to the sidelines and inteviewing, personalized clups from his rebeim, favorite singers, etc)
Proper lighting!
You will prob want an external monitor as it can be difficult to make sure you are constantly in focus.
Thats what i have off the top of my head. I am not a professional but i have done this BH for numerous familly simchos recently.
Many of the livestream concerts recently have been done by the same guys. You can try getting in touch with them.
Also Chananya Kramer of KolRom is highly experienced and naturally a very talented individual.