Again it is personal preference. From my experience, I would prefer a white colour anytime because if you are living in Karachi and you clean your car yourself then you would agree that dark colour such as black requires cleaning three times a day because atmosphere in Karachi is very dusty (so as in other cities of Pakistan as well). White colour doesn't look unclean even if it has lot of dust on it so it doesn't require much of a cleaning. Otherwise if there is no dust, black is a preferable colour or if you have cheauffer/cleaner available on 16/6 basis who keeps off the dust from time to time from your black colour vehicle 
Other advantages, scratches on paint don't prominent on white colour as compared to black. Maintenance is easy on white colour and spray can would help for many DIY activities.
