sure, theres a suggestion forum for ideas like this :)
I'd actually expand it, what if the world had 1 owner dissapear or nuke a franchise? it would reflect poorly on the parity factor even if the world was as balanced as any other.
Something like top 5 win totals, minus bottom 5 win totals, divded by 5 w/ a 5 year rolling average. Then allow that number to be saved so that it can be easily found so a prospective owner can see if a world is balanced typically or leaning towards a few teams typically. Perhaps what you see today in a world isn't what you'd expect from his 20 year history.