The client wants to use a modern door and sidelights: energy efficient, less expensive, tax credits.
That means that part of the entrance size is known: 60 inches wide, 80 inches high. The proportions and moulding of the door and the sidelights are also fixed.
The existing door is post-WWII, Mid-Century - and I read it immediately as such. I am not sure, even if I copy on old door exactly, that I can design a door that doesn't read 'Early-21st Century'.
The subtlety of a period has to do with tools, materials, joinery, as well as proportion, parts, and details. Weathering, layers of paint, dings (ie: being used for 200 years), matter too.
Still, I want to try, you know: such a fine challenge!