I think that right now, best city to write is Athens/Greece
Offers everything! Easy or hard streetbombing, never buffed. Easy or hard commuters, clean or dirty, any kind of yard lay up. Also the subway is on an uproar, fullcolor and dirty, looks like Rome or Bucharest, but there's still some space. Easy paint. Finally, for the "hard" ones, check out the metro, one of the hardest in Europe, offers super atmo underground yards, highly protected depots etc