My sister and I have just returned from the Avalon's Tranquility Tulip Time Cruise. It was her first visit to Europe and for both of us our first river cruise. We would definitely do it again.
The Tranquility is well maintain and cabins have ample space for clothes. Staff was attentive to your needs and meals were very good. There was an omelet station (if you wanted one) at breakfast as well as cereals, yogurt, cheeses, pancakes and breads for breakfast. Lunch was either sandwiches; served in the lounge; or buffet of hot dishes and salads served in the main dining area. Dinner was a choice of appetizers, salads 2 main course and desserts. There was a "standard" fare each night of chicken steak or salmon for those who did not want to try main courses of rabbit; chicken cordon blue and haddock.
Evening entertainment is limited. We did have a trio of string musicians play one evening and a crew talent show that was fun another night.
Your days are filled with walking tours of the towns you visit. Most times your docking space is a 20 -30 minute walk from city center. THe walking tours only allow 30-45minutes of free time.
Visiting both Floriade 2012 and the Keukenhof were the highlights of the cruise. Floriade being a mix of flowers and horticulture exhibits from around the world. The Keunkenhof was in full bloom and as it was our only sunny day the entire week it was magical. We did the full day at this garden and still did not see it all.
I would recommend river cruising no packing and unpacking; well appointed cabins and good food. Internet is spotty due to constant movement of the boat; but it's vacation not a business trip.