Booked the Oceania Insignia for its historical Black Sea ports which were cancelled due to crisis in the Ukraine. Although this was not the cruise lines fault they failed to provide any consideration to make up for the missed ports. We booked all our tours privately (except Sochi Russia) due to high cost and herding cats atmosphere of cruise line tours. The Sochi tour was an expensive waste of time and money. Called the highlight tour - Sochi has no highlights. Stalin's Dacha was the only thing worthwhile and it could have been done in a couple hours; of course the cruise line would not have made much on that. We took advantage of the extra night in Bulgaria and spent the night in Bucharest which was the highlight of our cruise.
We strongly advise experienced travelers to book private tours in order to save 30-50% and have a small group. It allows you to pick the exact places and times spent at each.With Cruise Critic and Trip Advisor there is no problem finding tours at all the major ports.
The Insignia is a fine ship with an outstanding crew and staff. Can't say the same for management. The food was excellent in all dining rooms. Entertainment was weak and enrichment lectures were tour talks.
The Oceania small ships are the same as the Azamara ships yet Azamara gives you better value in that they always include pre-paid gratuities, beer, wine, and spirits with better entertainment. If you like the small ships you really should give Azamara a try.