I'm so glad you watched and enjoyed it! I intended to last night, and opted for Killing Eve instead. 😏 I will definitely watch it today though.

'A' and 'B' are light fixtures hanging down approximately eight feet above the finished floor appropriate for the style of architecture; another fixture of the same design could be added between the two. I am afraid to ask the style of the house in fear of being attacked by hyenas. 'C' is a surface mounted non-heat producing fixture in the closet. No need for additional fixtures if the proper fixtures are selected. The location of fixture 'B' would be important if the door leading to the garage was moved to alleviate the door conflict. The locations for the switches for the fixtures (and other fixtures) would have to be worked out in the field; it appears little space was allowed for them in some locations.

I would ask for a drawing from the installer showing both options and if you want help here we need a to scale floor plan and pics of the flooring IMo the hallway would not have anything crossing it since the direction of the flooring is not changed in the hallway but in the bedrooms so I need some context .

Like Seabornman suggested, extending the wall is what I would do. Either the entire length/ run of the wall eliminating the ledge altogether or build out only the problem area at the top of the stairs. Starting at the last step before the landing. Then finish and cap the ledge.