Well, Paris is the greatest city in the world. So there's that. But it's also a better city for a person with a modest budget. The Parisian lifestyle is more accessible and is centered around public amenities/ social interaction. Between the parks, museums, cafes, river, architecture, neighborhoods, and people watching opportunities, you can be endlessly satisfied for almost no money at all. If you have money, and are really interested in nightlife, shopping, or sports, London may be a more suitable option.