My narrowboat, as was, not useful but I enjoy wallowing in the memory so here goes:
Mostly solo so able to just manage with only 60ft.
SF stove central in boat, both x and y. So lounge central also.
Galley at stern so that wife who does all our cooking was near to the steerer (on the rare occasions that she came on the boat) who was more willing to be out in the cold. Straight either side layout kitchen, with full 60cm cooker& hob on one side & narrow units including sink on the other.
6 seater dinette in between.
Straight sofa convertable to bunk beds in the lounge, NO "L" shaped sofas because I detest them. (The horizontal portions are too deep for my legs, the backs are not sufficiently near-vertical for me, and the angle is wasted space.)
Gas water heater in the lounge on the adjacent bathroom wall to minimise pipework to the shower.
Jabsco flush mascerating toilet connected to pumpout tank near the bow.
Bedroom with fixed double bed 200 x 140 cm so bigger than some, with 800L water tanks underneath.
6 seater well deck.
4 x 13Kg gas bottles in transverse bench locker at stern.
All services, pipework, wiring, etc completely accessible.
What will I do next time? 72ft. An automatic folding rigid canopy over the cruiser stern. Pale roof colour. But definitely same hull builder.