I've thought the Magazines page has been messy for a while now, though with collections now also being on the same page (at least for the time being), it's starting to get very out of hand.
Firstly, there's the main functionality of listing magazines. There are technically six sort options: subscriptions, threads, comments, posts, creation date (newest), and recent activity (or at least I think that's what active is). Two of these — newest and active — are separate tabs for some reason, and the other four are under the hot tab. And if you click one of those four while you're in newest or active, you'll be brought back to the hot tab. This lack of consistency doesn't make sense and only serves to make the page more convoluted than it is.
Additionally, there are also abandoned magazines and collections, which have no search functionality or sort options like the other tabs (which I assume is just a development priority thing). Having these alongside some of the sort tabs doesn't really make sense, and it'll make even less sense if they ever get their own sorting functionality (e.g., being able to sort collections by newest).
Now, I imagine that Ernest has stuff to do (e.g., federation improvements & new features) that's much more important than messing with page formatting. Should he ever get around to it though, my suggestion for improving this page is as follows:
Have only 3 tabs: all magazines, abandoned magazines, and collections.
Each tab should have the same sort options: most subscriptions, most threads, most comments, most posts, newest, and active.
Each tab should have a search bar.
I'd also consider changing the name in the header to something like "Browse Magazines" though that's nitpicking.
Thanks for the feedback, I've contributed sorting of the magazines and actually "the other four are under the hot tab" is not the case. They're not in any specific tab, they just sort by number of threads/comments/posts/subscriptions. I've done it this way to be backwards compatible with newest/hot/active tabs that were already there before introduction of sorting by clicking on table headings. Nonetheless, I agree that the Magazines page needs more polishing after recent changes and your suggestions are good.