Urban squares it can be of any form or shape but junctions and nodes can cater the situation. I wont say about Mumbai, but Navi Mumbai is safe. In Mumbai I can only say about queen's necklace. Since I live in Mumbai, we all know that it is a lively city because of the fact that it never goes to sleep. So collectively the city is safe. But.. when we talk about spaces.. landscape and street furnitures also play an important role to lay the urban as well as cultural fabric.. along with the nodes and junctions if we plan a proper punctures /pockets for landscape. It will be helpful in making space safe... also when we talk about planning there are very less amount of lights and an elongated vista in the terms of isovist... which makes the space safe during day time but unfortunately those spaces tend to be unsafe due to lack of street lights. Sidewalks and pedestrians would also contribute on a very huge level for that matter. Considering the fact that... people will change their lifestyle according to the way as design.... design and planning evolves mindset and psychology and behavioural pattern of human species.