I've been trying to decide whether or not to submit an entry for this contest. Unfortunately, OOTP is not yet ready feature-wise to adequately handle my ultimate fictional league, so as much as I'd love to do that, it'll have to wait a few years. Now that the deadline is just a day away, I suppose I'll throw an idea ou there. (Nothing like waiting til the last minute, eh?

)
What I ultimately decided to submit is similar to jmknpk2's Continental States League. The league would be known as the
Interstate Baseball League. It is essentially an alternate universe where real-life American players represent their home state or territory, as opposed to random cities. (Originally, I had wanted to do this as a tournament format, but I think it could be just as captivating as a regular league.)
Here are some of the basics...
OOTP VERSION: OOTPX
STRUCTURE:
Eastern Conference
Northeast Division: Connecticut, Maine, Massachusetts, New Hampshire, New York, Rhode Island, Vermont
Atlantic Division: Delaware, District of Columbia, Maryland, New Jersey, Pennsylvania, US Overseas (military bases), Virginia
Southeast Division: Alabama, Florida, Georgia, North Carolina, Puerto Rico, South Carolina, Virgin Islands
Central Division: Kentucky, Indiana, Michigan, Mississippi, Ohio, Tennessee, West Virginia
Western Conference
Midwest Division: Arkansas, Illinois, Iowa, Louisiana, Minnesota, Missouri, Wisconsin
Northwest Division: Kansas, Idaho, Montana, Nebraska, North Dakota, South Dakota, Wyoming
Southwest Division: Arizona, Colorado, Nevada, New Mexico, Oklahoma, Texas, Utah
Pacific Division: Alaska, American Samoa, California, Guam & Northern Mariana Islands, Hawaii, Oregon, Washington
MINORS: Minors will not be used, but each team will have a reserve roster.
LOCATIONS: Teams will play in their respective state/territory's capital city, unless a considerably larger and/or more centralized city is available.
STADIUMS: All stadiums will have equal factors and dimensions. (In fact, an attempt will be made to equalize all possible aspects of league play.)
GAME TIMEFRAME: Play will begin with the 2009 season and will run approximately 12 years.
REAL-LIFE TIMEFRAME I would start this league in January and run it through December, simming about one season per month.
FINANCIALS: Since players represent only their home state/territory, they would not be changing teams and would not be under contract. And since factors like market size and fan loyalty would be equalized, financials would be unnecessary and therefore turned off.
PLAYERS/PERSONNEL: Only American players/personnel and those from Puerto Rico, the US Virgin Islands, Guam, and American Samoa are eligible, although certain foreign-born players would be eligible if they were born on US overseas military bases. Players and personnel represent the state/territory listed for their hometown and may not play for any other team. Therefore, trades and free agency will be disabled. A mix of real players (from the 2009 MLB Quickstart included in OOTPX) and game-generated fictional players will be used. For those states/territories without enough players in the MLB quickstart to fill out rosters, fictional players (with lower ratings) will be created for the initial season. For subsequent amateur drafts, fictional players will be generated with ratings appropriate to their state/territory's baseball level.
While market size/fan loyalty/cash/etc. would be even, states/territories will have varying baseball levels. This will help to ensure that states/territories which traditionally produce more baseball players in real life (CA, FL, TX, PR, etc.) generate more and better fictional players within the game.
RULES/OPTIONS: TBA
I will elaborate on and will probably solicit feedback on rules and options if this league concept is selected. I'd like to keep as much of this as realistic as possible, but I'd also like to utilize it as an opportunity to test out a few experimental concepts, so there might be a few minor differences between the ISBL and MLB rules/options. (Incidentally, I would be using alternate nationalities and ethnicities databases for this league, so it would be a good chance to see them in action.)
Anyway, that's the general idea. Questions and suggestions are welcome.