As a follow-on to Paul's "positives/negatives" comment above, I'd like to point out that the site's internal search system is, and I didn't think it was possible, considerably worse than the old system's internal search function. I've tried a few different searches, things that should yield dozens if not hundreds of hits, and gotten no more than 10 results or so -- and I've yet to see Search return a hit more recent than 2012 or so.
Never mind, you might say, we got around that on the old site by using a Google site search, which worked moderately well (barring Google's bizarre refusal to allow you to sort the search results by date, but that's hardly GS's fault). Unfortunately the Google site search doesn't seem to interact well with the new site either, again giving very limited results. Maybe that's something that will improve with time? Hard to say. At the moment, though, good luck in trying to dig information out of the site if you don't already know exactly where and when it was posted.
Something else I miss: the old site let you click on your profile name and you'd see all the recent posts from your "friends". (Now we don't have "friends", just people we "follow"? Whatever.) That functionality seems to have disappeared; the closest I've found is the "New Posts" link at the top of the page, which shows you all new posts from everyone, regardless of whether you "follow" them or not. It works OK, I guess, but you spend more time weeding out the stuff you don't care about.