I've determined it's basically impossible to do that if you don't own a dedicated high-bandwidth seedbox. That costs a bunch of money, at which point you may just pay for another service (usenet) that has the stuff you want.
You have to maintain a certain ratio in all of them, but even though I've literally seeded everything I downloaded all the time, barely anyone ever connected to me, because their download need was already filled. Torrent clients prefer seeds with higher upload speeds. Thus I stayed at 0.0X ratio the whole time. Even when some of the files were designated as "free leech", so you can download and seed them to get your ratio up, that simply didn't work either.
Combine that with what you said with how hard it is to join them, they're just not worth it.
The whole concept is pretty stupid because of that. If there was a private tracker that simply looked at availability instead of ratio, sure. It's so weird to me how you would keep requiring ratio if all files are well-seeded.
Edit: the "dedicated" part was exaggerated, yes. However, "high bandwidth" means different things in different areas. Many areas in the world still have shitty 5 Mbit internet. Just because you personally are in the "lucky area" where you can do high-bandwidth seeding from home, does not mean other people do. If you can get much more than that at home, you're already in the "high bandwidth" group.