score:10
I visited Paris for the second time during easter last year, it was generally slightly more crowded than the first time I went (November 2016) but this could have been down to other reasons such as the weather.
The Eiffel Tower is actually open longer on holidays like Easter, extending their opening times to midnight. Source And the Louvre only alters their opening times at Christmas, so is not closed either.
The attractions such as those mentioned above didn't charge more, but some street sellers may do. I didn't notice any specific price increases.