Yes, that is the shallow draft keel. The design (known as "Warwick) after the person who thought up the idea) is supposed to retain the windward performance of the deeper keel. It was very fashionable at the time, but has fallen out of favour. a member of our club bought a 30 with that keel new in 2007 and still has it - very satisfied with the boat. I have had 2 shallow draft Bavarias, a 2001 37 and a 2015 33. The former was not very good - too shallow, but it was bought with a view to going through the French canals, but the latter, which I have just sold was very good. Difficult to say what sort of cruising speed you can expect as much depends on sails and then how hard you want to push the boat. They, like most Bavarias are family cruising boats and are capable of good passage times comparable with similar size cruising boats.
The interior should be dry as there are no obvious natural sources for water to enter the interior of the boat.. Can't comment on the heating system as it was a factory option and some dealers fitted stsrems locally. The usual is a hot air Eberpascher or Webasto in the lazarette as you have found with outlets in the aft cabin, saloon and heads, although there might also be an outlet in the forecabin.
The switch panel has individual switches for the 12v circuits with icons - the details are in the owners handbook. The outline of the boat just indicates which lighting circuits are on. all the other circuits should light up at the switch when on. The flashing light may well be indicating that the water tank is empty. Have a look in the Downloads section of the Help secrion and you will find a downloadable copy of the handbook and wiring diagram on the second page.
Good luck with the survey and hope yu become another happy Bavaria owner.