By "Overview of complete season" I'm thinking in terms of a walkthru of an entire season, hitting all of the actions one would take part in... spring training, setting lineups, doing roster moves, trades, hiring staff, scouting, free agents, etc etc... and on and on through a full season. There's a lot that can go on during a season and for a new player to see how, when and why those things how, where and would/could/should be done might be most helpful. And be presented in a reasonable amount of time.
An overview of historical leagues and how they work is also a good candidate (and a second place choice for me in this poll) since many new folks initially come from that direction. Something explaining how to set up your league, what the related options are and their effects. How and why this isn't a single season replay locked into certain player performance results but instead is the start of a multi-year career league that can (and will) deviate from history is important to understand up front. Highlighting and explaining the differences between OOTP and single season replays then tying that back to how various options can be used to narrow or expand the variations you'll see in OOTP historical leagues. Could be helpful but not to the level of a complete walkthru of an entire season, IMO.
While a tutorial setting up the league might be a good idea, I think that can quickly get too complicated and long. There are so many options and dependencies that it could easily be too much to tackle correctly or just run on for hours and hours and bog down in tons of detail, options and relationships leaving someone in a state of MEGO (My Eyes Glaze Over). Yeah, I have the attention span of a knat....
