A simple all galss dor with a wood frame either in finished wood or paintable and then replace the screen door with a phantom screen to get the max light Cute house BTW but needs some work espec\ially on that little step in front of the door I think maybe think about raising the whole porch floor up and then new entry steps and maybe be able to save the railingand posts and install again.

Absolutely, a full glass door like the one below would work.

Grover Condos · More Info

But I think a door like this would be more in keeping with the cottage style of the house. For all practical purposes, it allows as much light as a full panel glass door.

Fox Hollow Residence · More Info

Full House Renovation · More Info

Another thing to experiment with might be to keep the door open and see how much light gets in at certain points in the day. If he has mature trees and that porch overhang, even a 'full view' door might not help a lot. Dunno.