I haven't used this company, but dealt with tripsite.com. The logistics should be similar. If you aren't interested in biking (at least on most days) on a bike and barge you are mostly out of luck. The bike generally takes you from one place to the next while the barge sails. If you stay on board, you can enjoy the view, but not that much more. The barge has to deal with locks, and sometimes to pick up people part way through the day, but if you stay on board you won't get too much chance to do anything until mid to late afternoon when you dock in the new location. (Because the small crew does everything - sail the boat and look after breakfast and dinner - the barge sails during the day and docks at night.)
In terms of the level of luxury, Tripsite grades their barges by level, from standard class through comfort level, premium and deluxe, with prices generally commensurate. (I travelled on a deluxe barge, the Quo Vadis, which was very nice, but not at the Ama or Uniworld level.) They also have some small ship cruises, without biking, although I'm not sure what activities they do.