well if the NBA does expand again, I would like to see Seattle and either Kansas City or St. Louis. Then you would have 16 in each conference and you would have to realign to four 4-team divisions.
EAST
Northeast
Boston
Toronto
New York
New Jersey
Mideast
Washington
Philadelphia
Indiana
Memphis
Great Lakes
Chicago
Milwaukee
Detroit
Cleveland
Southeast
Atlanta
Charlotte
Orlando
Miami
WEST
Southwest
San Antonio
Houston
Dallas
New Orleans
Midwest
Minnesota
KC / St. Louis
Oklahoma City
Denver
Northwest
Seattle
Portland
Sacramento
Golden St.
Pacific
LA Lakers
LA Clippers
PHX
Utah
Then you redo the schedule to emphasize division games and rivalries. For this I will use the Spurs as my example
Spurs play 82 games
vs East: 2 games x 16 teams = 32 games (16 H, 16 A)
vs Southwest: 6 games x 3 teams = 18 games (9 H, 9 A)
vs Midwest: 4 games x 4 teams = 16 games (8 H, 8 A)
vs Northwest: 2 games x 4 teams = 8 games (4 H, 4 A)
vs Pacific: 2 games x 4 teams = 8 games (4 H, 4 A)
the next year they would play the Midwest 2 games each and Northwest 4 games each....and so on.