Looking for advice on hardware upgrade

Hello!

I've been editing for years on a 2013 iMac with 32GB ram. It was a hand-me-down from another department at our company (because that's what they do!) It's always been temperamental, but now that I'm using it to work from home doing larger, more complicated projects than before, it's almost impossible to use. I do a lot of music work with sometimes 40-50 tracks of video playing on screen at once. Even with proxies, the footage hangs up and won't play smoothly which is a major problem when trying to cut to music.

I've been told that we might finally be able to upgrade to a system better suited to our needs, but I'm supposed to make a recommendation for what to buy and honestly have no idea where to begin. Obviously, the recommended specs on the Adobe website are for projects that aren't quite as insane as the type of stuff I'm trying to do. Can anyone give me any advice? Thanks so much!