Don't know how useful this is going to be to the discussion, but here's my two cents.
I started the league I run before I really ever joined the forums here. I did have the benefit of being in three (non-OOTP) leagues at the time, which is where I started my recruiting from. I did ask the commissioners of each league if they minded before I sent out a league-wide e-mail. The last two or three spots were filled by people recommended by the initial recruits. I've gotten lucky. I've only lost one owner in the year and a half I've been running the league, and one of my owners has become an active member of the KBL as well.
I like to think that, if I were to start a league now, I have a little bit of reputation to go on. Maybe not so much on these forums, but in the leagues I'm a part of. Someone will undoubtedly smack me down if I don't. But I think that's a big part of it: having a bit of a reputation. If you're advertising for a league on these boards, it's very helpful to know a few people that can vouch for you, even if they're not joining your league. I know that when I joined the KBL, I didn't know much about anyone involved in it, other than that I'd made a trade with kq76 in the UBL when we were both members, and he seemed like a good guy. Add to the fact that he was a post count Hall of Famer here, and I took a shot. I haven't regretted it.
My own personal priority list for what I look for in a league starts with making sure it's fictional, but after that, I tend to look for professionalism. That encompasses website, rules, owners/commissioners and board demeanor. I've seen a lot of leagues I'd love to join if I had the time, and I'm guessing a lot of people that frequent fictional leagues are in a similar boat: they're booked solid already.
Anyway, I've rambled on long enough.
