Oh! You are blessed! What fun you are going to have reworking your Contessa.
I recently constructed cabinets in the V-Berth that are a great success and there are photos in the Gallery. However, to pursue the solution below they would have to come out and I am reluctant to deconstruct my good work. However it is VERY tempting.
I did some doodles recently and think that I could rework the Contessa interior to make a more functional boat. While it is possible to seat four around the current saloon table, it is at best awkward. I prefer to think of my boat as a two-person boat with the occasional larger group for parties. Given this assumption, the goal is to install a dinette in the main cabin, offset to Starboard. You will need to measure again of course but this was what I was considering:
Relocate the hanging locker one bulkhead forward, cutting into one 'head' of the V-Berth.
On your 1974 and my 1976 the icebox is on the starboard side. Remove the icebox and relocate same in the former hanging locker.
You could consider a cut-out in the bulkhead between the port-side galley and the new icebox. You will need a pillar between these two areas of the boat because it is part of the mast support. You may also require additional reinforcing to support the cut-out since this would be in the main bulkhead. Alternatively, fit a low fridge or even a pull-out drawer as an alternative to the current top-opening solution. Then one could have a small sink and/or additional stowage in the former hanging locker.
Remove the old icebox completely and replace with seat which faces both aft and to port. The design of the seat will be important as where your head and shoulders contact the head-liner will be critical to comfort.
You will need to cut into the quarterberth on the starboard side so that you can place your legs. Things will still be tight and when using the dinette one's legs will most likely rest partly on the centre aisle and partly in the area of the stowage beneath the former quarterberth.
You have a choice now -- you could fit a fixed seat facing forward and to Port opposite the new seat -- the table will fit between the two seats. To do so, while respecting where your head will fit against the aft end of the cabin, will create a large dead space where your legs would have been in the quarterberth. This would be a great place to stow sails, and other large bulky items.
Alternatively, you could construct a seat from stiff foam. It would probably be 12" thick as a minimum to get stability. This would be installed with velcro. The attraction of this foam bulwark is that it can be removed making possible the use of the starboard quarterberth.
Finally, were one to arrange the new table top so that it could fit securely between the seats, one will have effectively shifted the starboard berth forward. Using fold-outs or pull-outs one could then turn the starboard berth into a good-sized double berth.
I suppose you could undertake the same project on the port side but it would require visiting the location of through-hulls and sea-cocks.
I would love some discussion on this subject -- has anyone else tried something like this? Can it be done? Would it be useful? Would it kill the resale value of the boat? And how annoying will it be to whack my head on the dogs of my nice bronze portlights when seated in the new forward seat?