My entire career of event videography for live and tape-delayed /edited coverage of News conferences, weddings, business conferences, social gatherings, the number one problem to solve first is getting good audio; getting tapped into the “house” system, avoiding hums and buzzes, and getting my own mics placed wherever I need them most. Lighting comes second.
I wrote at length before about all my tricks for capturing clean audio before, if you want to do a search. My preference is always for hard-wired sound solutions and I look at wireless as a second-best option only, because RF-based solutions have let me down enough times to make me not trust them.
Lighting, you don’t always get a say on, but always try to talk to the people putting the event on about windows at the venue and what the back-lighting issues might be.