I think you should provide newcomers some kind of instantaneous fun, since many players can create their teams and wait for several days for a game. If someone starts before the all star game, for example, it can take like 5 days for his team to play for real, since the newcomer won't be familiar with the idea of scrimmages and everything.
What I mean is: a newcomer should be given the opportunity to start playing a few minutes after he gets his team. He could be offered the choice of, for example, playing against himself a few times, when he wants, using his own players, just to feel the game, before his interest fades out when waiting for the real stuff. He could also be offered some nice features, like a 3PT competition using his own players, just for fun and for him to start to feel familiarized with the game.
Just some ideas, I hope it doesn't sound stupid, but I really think that something should be done to avoid newcomers to abandon the game just because he is not able to have some fun quickly.