Yes - windows are very important - they are the eyes of the house and sadly homeowners are being brain-washed into believing that they need to replace their windows. The improved insulation factor with a replacement is a scam. No one ever thinks about the importance of the design details of the window, the golden rectangle, and the proportion of the casing. Window manufacturers don't care so it is important to get the word out and educate the homeowner. Many architects don't even follow these rules.
I explain this in my website http://www.OldHouseGuy.com/windows
At the bottom of the page I have a link to historic window restorers. If you have a qualified referral, please submit the info. We can all help save our older buildings this way before homeowners opt for plastic windows.