They are all good schools and are located in important and interesting towns.
Depending on what you like to do in your spare time, and at what time of the year you are going, some are better than others. Some are geographically better too, from the point of view of weather and temperatures.
Going from North to South:
Lille is in Northern France. Big city but weather in the winter can be bitter. Easy to hop over to the UK as there are direct trains to London via the Channel tunnel, or to Belgium which is a few miles up the road with Brussels thirty minutes away by train.
Strasbourg is North-East. It has a wonderful medieval centre, with picturesque canals . Headquarters of the EU so lots of people from different EU countries. Just across the Rhine from Germany. Characterful little towns nearby surrounded by vineyards.
Paris and Cergy-Pontoise (Paris suburb) would be the dream of most people because it is the capital of France and has so many attractions, cultural and other, that there is always something interesting to do.
Geographically Rouen is not far form Paris by train but is the main city in Normandy. Another huge town which has a medieval core and beautiful historical buildings but in the middle of a pleasant rural area. Not far from WW2 landing beaches and the world famous Mont Saint-Michel.
Toulouse is right down South West on the river Garonne. Another ancient town with interesting architecture but a modern "space city" on the outskirts as it is the centre of the French aero spacial industry where the famous Concorde was built. Not far from the Pyrenees mountain range and Cathar country. Much warmer than any of the previous towns.
Nice and Aix are South East. in the Provence region. The light is remarkable and the temperatures there are exceptionally pleasant.
Nice is on the Mediterranean coast at the heart of the French Riviera and attracts hundreds of visitors annually as it is a popular holiday destination.
Aix is a wonderful old city that attracted painters from the world over and has everything from Roman remains to modern architecture. It is near several other picturesque ancient towns with Roman architecture and close to the French Riviera.
All these towns are great places to study in. They have outstanding universities so are full of dynamic young folk, and there are masses of things to do in each and every one of them.
You really are spoilt for choice. Have a closer look at them by googling them and choose the one that appeals to you most. Studywise they are equally good, though on a CV for the future Paris Dauphine would look good because it is in the capital and everyone has heard of Paris.
Personally if you were my daughter I would advise you to pick between Paris or Aix- en-Provence.