Do I buy the new Business and Hobbies EP or wait?

I think it's worth it, personally, but I have a lot of other packs.  The bonus items will be available for a month, so take a day this weekend or a few evenings and watch someone's Early access Let's Play on YouTube (if possible, a Sims YouTuber that plays similar to the way you do) and see if you like what you see.

There's a thread that lists a bunch of early access videos, so I'd start there to see who you want to watch.