Thanks for all the replies, looking at them makes me realise that I perhaps worded my initial question a little vaguely.
One of my main concerns would be efficiency of any appliance we may have. I incorrectly assumed that 12v would be inherently more efficient that 240 volts.
I also want to have the option to CC in the future without being reliant on a shore hook up
I do like the idea of having a 12 volt system with a decent battery bank and inverter, and the suggestion in one of the posts to have a backup or alternatives.
One thing we have decided on is to have a multifuel stove with a back boiler and a separate diesel heater like a webasto to provided heating and hot water.
We would boil the kettle either on top of the multifuel stove or the hob, which would elimante one power hungry device.
I think a twintub would probably suit our needs, we don't use a tumble drier anyway so I think we can rule that out.
I can build a pc/desktop to run off 12volts or use a tablet for most things internet related so that shouldn't be an issue. One of my hobbies is PCs/Linux, so I may build a Raspberry Pi based system for the boat.
When I said creature comforts I didn't really explain what I meant, and I suppose creature comforts can vary from one person to the next. Creature comforts for me often just includes a roaring fire, a good book or album and a decent single malt
We're not too bothered about TV, we have more channels that we watch as it is and often find ourselves watching things using catchup so we would probably go down the netflix/youtube route.
We're far more likely to listen to the radio than watch the telly. A definite creature comfort would be to have a decent turntable on board so I can keep my vinyl.
So that leaves the fridge, I have seen another thread on fridges so I'm going to head over there to read it rather than go into it here.
Thanks for all the tips and suggestions. The discussion has been very informative, given me lots to ponder over.