We have just undertaken a cruise on L'Austral from Venice to Croatia and back to Venice. We were very excited to go on such a brand new ship. We stayed in a normal cabin while our friends booked the owner's suite. Hopefully they will write their review but they spent many hours talking to the hotel manager about things that were unacceptable. For me the outstanding point was that it was like walking into an old age home! There were no children or anyone under 50 years of age. I would recommend anyone younger to check first what the composition of the cruise passengers is like.
The cabins are very small and the double bed occupies most of the room. Our room had only a shower and no bath. Service levels in general were not great. While the food was generally very good the service in the main dining room was shocking. The few waiters could not cope and we waited very long for our food. We eventually booked dinner in the buffet restaurant on deck 6 to avoid the long waiting. The 2 nights that there were cocktail functions before dinner with the captain and then dinner for everyone in the same restaurant were chaos. Also the Tauck group seemed to get preferential bookings at dinner and special functions where bars were closed for their functions. I found that totally unacceptable as I was a fully paying passenger!
Croatia is beautiful but my impression was that the excursions off the boat were very expensive. We took one cycling excursion near Dubrovnik which cost Euro 75 per person and which was certainly not worth that amount. We ended up renting cars on our own in the other locations and definitely saved money doing that.