I completely agree about us cafe-ers being a lot more knowledgeable about rising stars/prospects and being able to snag most, if not all of them before our league mates do. That said, i play 2 public leagues and 2 friends leagues every year, all 12 teamers.
If you're in a public league, it'll either be very competitive, or anywhere from 2 to 6 of the 12 managers end up not following through/barely changing their lineup.
My friends leagues, however, we're all very competitive. A few of my friends use the cafe, fanball, rotoworld...you name it, we use it.
All in all you can see a huge difference in the people who use outside sources like the cafe and such, versus "normal" players who just follow Sportscenter. I know my teams have gotten better over the years since discovering the cafe.
You'll also have one of those years where one or two of your teams get stacked, because a lot of your waiver pick ups outperform expectations, and you're able to deal the studs you drafted for other help on your team, knowing that your waiver studs will help keep your team afloat. That's the case with me this year with guys like Lincecum, Shields, Reyes, Hudson, Accardo...or when someone dropped Erik Bedard in his slump and i nagged him. And the trades you pull off are extremely important (example, i just snagged Hafner for my Abreu/Hudson). The stacked team in my sig shows that i had to get lucky in waiver pick ups and trades to come out with a more than balanced and pretty stellar team.
Bottom line is, it all obviously depends on the people you play with.
12-Team Yahoo! H2H Keeper League - 3-Sport Dynasty - Year 4 - Jonny D's Team
Keepers: Albert Pujols/Jose Reyes/Ryan Braun/Grady Sizemore/Evan Longoria/Tim Lincecum = SWEET!
#25 - Barry Bonds - 73, 762