Anyone who has played games like this knows that some have a Hall Of Fame for legendary players. What better than to give each league the ability to induct former players into the Hall Of Fame in their universe? Maybe have it be voted on by each owner several preseason to vote on a few players worthy of being selected.
We have a hall of fame in ncaa that is voted on by all 32 owners each year. You need 75% of the votes to make it. Here's the link to the inducted players so far :)
The USFL/WFL will have a Hall of Fame as soon as I can find the time to compile a ballot, have the Hall of Fame committee approve it, then send it out to our membership for voting. This will be our first class.