The last photo is the dark hardwood at the new bathroom threshold. The bathroom project is a topic for a later post, but in a nutshell, we redid the whole room over the course of 14 months. The flooring is hardipanel smooth cement board, along with the walls and ceiling. I was able to install the cement board flush with the original hardwood in case we are able to save it.
I have removed all the Gened up baseboard trim in the downstairs hallway and revealed a lot of plaster damage. We have yet to install any thresholds downstairs yet until we fix these plaster issues and really tackle the hallway as an individual project. We may just add a layer (to the layers of history) of homasote over the existing plaster which would allow me to avoid any more trim installation. So many modern remodeling plans, so little time.