I have read several posts that certain places are best to do early in the morning. We will be spending two nights and are wondering which would be the best two to pick to avoid long lines. Eiffel Tower seems to be one. We are first time visitors - we would like to see as much as possible while still having a relaxed visit. We would also like to do a river cruise, but have heard that it is also beautiful at night. Also, we have considered a Moulin Rouge show in the evening - would our time be better spent elsewhere given our short time there? Thanks.