The Moscow to St Petersburg Cruise on Viking Kirov [now called Truvor] which my wife and I took cost us £6000 not including spends. We were impressed that so many excursions were included but these were all to tourist traps apart from the optional "home viisit" which sadly we missed but which we were told was superb. 90% of passengers were American which suited me fine better that having 90% Brits in my opinion.
many of the problems were not of Vikings making these were mainly caused by traffic particularly in Moscow. Our flight Heathrow to Moscow was 3.5.hrs. Coach from Moscow to Boat 25k or 15 miles took 4 hrs. Again not Vikings fault but not a good start. Traffic in St Petersburg was not so bad.
Russia does not have a good tourist infrastructure other that in Moscow and St P. HoweverThe Kremlin and Peterhof were highlights. Along the river there were only touristy villages and towns with endless dolls for sale. There were only churches/monasteries/cemeteries etc to visit along the river. I would have welcomed a trip to an Accountants Office for some light relief.