I went over Valentines a few years ago and it was great. A lot of the Fastpass machines were down because it wasn't that crowded. Valentines is fun because all of the princes are out with the princesses. I think you'll be fine on Tues, Wed, and Thurs. Friday & Saturday will be more crowded because they always are, but with Presidents Day the next Monday you'll get more people there for the holiday weekend.