This was my first "river" cruise (in quotes because we did not actually sail on a river, but instead around the Venice lagoon) and probably also the most "luxury" cruise I've taken. Next would probably have been my transatlantic cruise on Azamara a few years ago. I've done lots of ocean cruising, mostly on Celebrity but have also done Norwegian (next most frequent), Princess, Royal Caribbean, and Holland America in addition to Azamara. This was by far the smallest ship I've been on.
The cruise was a one-week Venice-based itinerary. It coincided with the highest "aqua alta" Venice has experienced in 10 years, which threw some curves at the cruise staff as they tried to adjust our itinerary around the high water. Luckily we had several days during the week where it didn't rain...much!
I mostly sail solo, and this trip there were a large number of solos on board (so far as I know, all women) due to a no-single-supplement deal Uniworld offered. I thought Uniworld worked very well for solo travel. They did offer a singles meet-and-greet one day midweek, but I didn't attend so can't report on that. Because of the small number of passengers and the open seating at meals it was easy to meet others and find a congenial table for each meal. I felt like the price I paid was an excellent deal for the cruise, though my budget and skinflint tendencies mean I will need to really keep an eye out for bargains if I want to do another cruise like this!
Small, but very well designed. Nice bathroom with excellent water pressure and nice shampoo etc. Bed was very comfortable. TV had many excellent movies and lots of TV channels. Everything was always very clean and well-maintained. Jar of chocolates on bedside table!