This is a very interesting topic. It seems evident that it would be much easier to pull off a good solution if you were starting with a CS 20 and the added length and beam.
I tend to like the more traditional looks of this type of cabin with side decks, if you are ok giving up interior space and volume of the Mk 3's.
If your were to start a new build, are the plans for a CS 20.2 actually availabe?