I have the below layout for the main floor. The floor is 60Y old hardwood floor installed without and transitions in all the rooms excepting bathroom and kitchen

There is porcelain tiles and a transition (the tiles are higher ) in the kitchen and there is old linoleum tiles in the bathroom (which is next for renos) that will be replaced with tiles soon.

There are some short stairs that lead to the double doors you see at the right side of the picture

The foyer that is next to the entrance is where the short stairs land (from there you can either get out of the house or turn right and along the bottom (in the picture) wall you can take stairs to the basement

There is no subfloor and the plan is to remove the old hardwood room by room and to replace with new hardwood.

The question that I have is this

-Are there any drawbacks for the plan to start replacing the hardwood floor room by room starting from the smaller rooms (the left side of the picture) ? I am told that I need to be careful with the reference lines (chalk lines) that I need to draw when I start installing the floor. These need to be somehow parallel with all the east west (of the picture) walls. That is a good point but I already have a reference there ...that is the existing floor. There is practically an uninterrupted line of floor planks from the left side accross the hallway all the way to the living. If I start installing from one of those lines to the north side and south side of the picture then this should work. Am I missing anything here ?