I'm starting a series of cruises which will include a segment from Amsterdam to Basel on the Crystal Bach (after Eastbound TA on QM2 and returning from Barcelona on Crystal Serenity).   I do mostly ocean cruising but have a little river experience.  My only European river past is in 2004 on Viking, Budapest to Nuremberg  but I've also sailed the Nile and Yangtze (both Uniworld) and upper Amazon, plus several North American rivers, mostly on small ocean ships.   I'll mention a