The thing is, different people gets offended by different things....
To add to the complexity, offensiveness can be of "n" number of dimensions. There are many ways a person can get offended in many different contexts and in many different conditions, situations, timing, mood, weather, etc....
What's offensive within a particular set of parameters may not be offensive in others.....
A picture of a baby would provoke a reaction of of love to a newly wed couple but provokes a reaction of offensiveness to a couple who just had an abortion or miscarriage...
What you should seek is not offensive photography but provocative photography... Something that provokes a mood, be it offensive, exciting, funny, etc....
A good photo provokes different reactions from different people
They may not be the same reaction, but they provoke a reaction.....possibly an offensive one.
The more varied are your viewers reactions, the better you are a photographer.....
Photography is like a movie, if your intention is to provoke one kind of reaction and you do it too obviously, you would be a B Grade movie...Go watch a B Grade movie and you'll know what I mean. The story line is cliched and it is very obvious that they try to provoke a certain kind of reaction. Leave it a bit open to interpretations, a bit more witty, from a fresh perspective and less cliched and things will improve.....
What is offensive to Singaporean? Look at the cliches and twist it around a bit, add some witt, add some humor, color, perspective....