Our Avalon cruise did not disappoint.Our room was comfortable and sufficient for the small amount of time we spent there. It was nice, 'tho to be able to open the door and see the world go by. I would not have enjoyed the submarine level as much. The meals were excellent, with plenty of choice and the staff always helpful. Happy hour at the bar was excellent value and the wine plentiful at dinner. For us, the best part was the quality of the shore excursions. We saw so many amazing places! We also attended every extra talk etc offered, met some lovely people who made us feel included, even tho not travelling as a couple, and loved every minute of our 'Romantic Rhine' trip! I have written a comprehensive review on trip advisor but I'm not sure if I'm allowed to place a link here. I ended up posting it on the TA Germany forum, so some googling should find it.
We only took one additional excursion - the Keukenhof tulip gardens in Holland, as we happened to be there at the right time for this garden extravaganza. It was worth it ... but we did not feel we missed out by not doing any of the others. But then we are fit and adventurous and did our own 'extra' tours of most places. Only word of caution - beware the map you are given in Strasbourg -the ship's docking location is marked in a most confusing way. Yes, we lost the ship on one of the above mentioned self guided extra excursions! All was well, as a taxi got us back well before sailing time!