Honestly, I would say that anyone who makes keyboard files,s hould keep releasing them. And sorry, but you were kinda wrong about "everything has been stepped". I find that hardcore, grindcore, mathcore, and other obscure metal/hardcore derived genres barely get ANY attention. Similarly, IDM and other obscure electronic genres barely get any attention. The few times I have gone looking for a sim lately, I just haven't found it, because nobody has made it. Sure, there are some things that are way overdone, just look at the new files section on BMS, but the obscure stuff is still REALLY difficult to find.
My big issue is that the community is way to fragmented now. We've got the guys like Glove and all the rest who release insane keyboard files, and then we've got the million people who make pad steps, and then we've got a whole bunch of people who are amateur players making amateur keyboard steps, but there's no real place that serves like a0 did. I've been consistantly disappointed with the new simfile authors. I really wish Reach, Toph, Skor, Snoc, Kilga, HST and the rest were still making files and that ther was someplace like a0 that served as a fairly centralized place for people to release those sims, because those authors are IMO WAY better than Glove and all the other ODI/whatever that place is called (I've forgotten). They're just getting to the point where all the keyboard sims are hard for the sake of being hard, and including triples in every difficulty. Sure, those files are challanging, but they just aren't fun for me. If you took Toph and all the rest and had them making harder sims than they were, that would be perfect.