At the risk of being unpopular, I would suggest splitting the nights between two hotels: the first night in downtown ( using points ) and the second night at the airport ( $145/night ). You could stay in central Paris all day on the 11th, have dinner, see a show, and then start heading to the airport, late at night. Sleep in next morning, have a long breakfast, and be at the ticket counter at about 12:30. This would give you enough time to get all your VAT refund done before departure.
It really does not pay to stay at downtown hotel the night before departure: all you'd have time for is breakfast. Why pay double vs. the airport rates? But... it is your call.