I have been to every team’s Arena / Stadium in all four sports. All 123 teams (and a few that no longer exist (eg Montreal Expos, Atlanta Flames)
160 facilities in total (many teams have moved into new places).
I do have 8 to get to so that I have been to their current arenas / stadiums. Plus there are 4 new ones coming in next year (Golden State, LA Football, Las Vegas Raiders and Texas Rangers)
Best ones - there are many
Worst - Oakland