We need a really interesting house this year. Something which is very BB5 in terms of the layout - but the decoration should be different so its not just copying off BB5. Like everyone else, I'd love to have an upstairs area, maybe for the diary room for more privacy and if there was some kind of balcony overlooking the house it would be good - if say there was a little snug there.
Like Matt said, it was great when the bedroom was outside, so maybe something like the kitchen being outside would be interesting - but the only niggle is if the housemates have to stay in the house they wouldn't be able to eat or drink.... starvation task anyone?