Having a house that is essentially solid wood has advantages and disadvantages.
Because there's no interior drywall to put things behind, all wiring (and plumbing, for that matter) would be exposed. X-House provide a baseboard system to help hide wiring, but there's a better way.
As suggested by the builder, Janne W, we will run flexible conduit under the floors and above the ceilings as the house is being built. That way, all of the power outlets and wiring for appliances, radiators, and toilets can be run below the floor and just surfaced where needed. Above, we can run wires for light fixtures, the heat pump, and maybe a ceiling fan, too. Our electrician will come in and actually run the wires and do the detailed work, of course.
The only wires we would have to fix to the walls would be for light switches, and a bit of care around door jambs should minimize unsightly wires running up and down our walls.
This means we will have to decide beforehand where we want to put outlets and fixtures. That process is underway with pencils and yellow pens on an A3 sheet of paper right now.