Thank you very much for your comments.
Unfortunately, the side panel did not come with a leaded glass insert, but it has the same "frosted glass" as next to the insert in the main door. Maybe that's the common last name...
The windows are made of white plastic, and we live in a bad weather area. We liked plastic to match the windows and found it easier to maintain. We both work full-time, so I can't take care of more than what I already have (like the wonderful kitchen )... and wood MUST be maintained, I see that at my grandparents'...
The staircase was planned 100% with the carpenter, we didn't like the round post he initially designed at all, and now we are completely satisfied...