So I'll start by saying this is probably my 15th or 16th cruise. I've sailed big ships on Celebrity, Princess, Royal, & Norwegian; and mid-size ships on Regent, Seabourn, and Azamara. I LOVED the Reflection!!
The ship is absolutely beautiful, immaculate, and offers everything I wanted in a getaway from the cold. We decided on AquaClass because of Blu, and it was perfect! I really feel we had the best of both worlds: all the entertainment and wonderful variety of music and bars that you only get on a large ship, along with the "country club" like dinning you find on the smaller ships.
Don't go for the itinerary, it's awful. You get to San Juan too late to do much, St. Thomas was just OK, but there were 7 (yes really 7!) mega ships docked in St. Martin while we were there. We tried to get off the ship, but the crowds of people looking for transportation was far beyond what the locals could manage. We gave up after an hour, and spent another lovely day onboard a lovely ship.
I still prefer a smaller ship for going to places I actually want to see (I booked my first Silver Sea for June in Europe), but for a warm weather getaway in winter, I'll be back on the Reflection!