Mixed league references aside, allow me to present the argument that the best way to fix the problems of offensive team owners is to change the ownership model away from individual owners and towards their communities.
One not often touched-upon fact is that the Green Bay Packers football club of the National Football League is unique in American professional sports. Its ownership not being being held by an individual or investment group, but as a community-owned franchise:
Quoth Wikipedia:
The Packers are the only community-owned franchise in American professional sports major leagues.[22] Typically, a team is owned by one person, partnership, or corporate entity, i.e., a "team owner." The lack of a dominant owner has been stated as one of the reasons the Green Bay Packers have never been moved from the city of Green Bay, a city of only 102,313 people as of the 2000 census.[23] While the team is operated as a non-profit organization, technically it is a for-profit corporation because under Wisconsin law non-profit corporations cannot issue stock.
[...]
Green Bay is the only team with this form of ownership structure in the NFL; such ownership is in direct violation of current league rules, which stipulate a limit of 32 owners of one team and one of those owners having a minimum 30% stake. However, the Packers corporation was grandfathered when the NFL's current ownership policy was established in the 1980s,[26] and are thus exempt. The Packers are also the only American major-league sports franchise to release its financial balance sheet every year.
The NBA, along with other leagues, could do far worse than use the Donald Sterling mess as a perfect opportunity to allow and encourage other teams to do likewise.
Of course, when Big Money is involved, good ideas take the back seat...