Hello, I got into this project maybe too late but it was interesting, I like the exterior look of the building so I wouldn't change much, just match the elements that are already there (I placed some notes in the plans). The floor layout I think is pretty self explanatory, I left the two entrances as they are so you can have more circulation options and since you are gonna rent it as a B&B is better that they have a key to the outside door an can't get into the other floors since you have control over the door that communicates with the inside, and when is not rented it works well too so you don't have to get out and back in to access that area, also I left the bottom of the stair visible as it would bring more volumes to the inside and make it more interesting, the fireplace as I said before I like the outside so I wanted to bring some of that to the inside, now with this I don't think we were really allowed to do a full interior design since apparently you only paid for the floor plan but try to combine some of the exterior elements with the ones on the pics that you showed as examples so there is overall relation and you give it a more timeless classic-rustic-industrial look which is what you wanted. So I hope you choose my layout or at least find something that you like here even if it's not mine and best regards.