Robinson World rolls in 13 days. I highly advocate it as being as good a Public World as you will find in HBD. Only 3 openings each of the last 2 times it rolled over. Season 14: 1 100-win team (102) and 1 100-loss team (100). With 4 games remaining in Season 15: 1 100-win team (104) and no 100-loss teams (one with 99, second worst 95). Different champs almost every year.
If you're willing to wait, it's a fantastic place to learn. I have 4 teams, and my Robinson club was my first, and I feel like I really lucked out learning in that World.
Only drawback is that the World Chat page is dead as a doornail. Our entire S15 chat (with the regular season ending tomorrow) is 3 1/2 pages of all-business posts like "Willing to trade Joe Johnson for a solid 3B." No banter at all, and very little activity after Spring Training ends.
Active owners who work hard on their teams, with a lively Trade Chat, however.