Paris has extraordinary palace hotels, but the best match depends on what you will use. A famous address does not guarantee a quiet room or an open view. The smaller hotels trade grand public spaces for privacy; the larger ones offer deeper dining and service.
THE SHORT ANSWER
Match the hotel to your trip.
If the hotel itself is the occasion, compare the George V with Cheval Blanc: classic dining and scale against contemporary rooms and a longer pool. If you plan to be out in the city all day, check whether you would actually use what those rates buy.
Ritz ParisThe Ritz history is worth another visit when the people make it feel lived in rather than preserved.
Hôtel de Crillon, A Rosewood HotelThe beautifully furnished suite and cool courtyard need several days to justify this address, not a brief visit to a famous lobby.