I would do a glass splash back [ this can be painted in your color choice to suit the decor ] - taking from the bench top up to the bottom of the range-hood on the wall of the stove. The window is beautiful and I would give anything to have them in my kitchen. I would probably paint OR stain and apply marine grade vanish to the would so that any moisture would not be able to ruin the wood. I would also put herbs or flowers there. Could it be made into a servery for outside maybe ???

Nothing will affect the feel of your house as much as the quality of the light. If you can at all swing it, keep your divided lights. Looking at your photo, those windows are gorgeous. Can you place glass on the exterior? I have some lead light windows in 2 locations. I made new frames with the leaded old glass on the inside and plain glass on the outside. While not as weather-tight, it's much better than single glass. While not as neat as your present windows, the new windows that have the interior and exterior lights with the spacers between the glass also look great and are at the present standards for energy efficient. We live in the PNW and used Milgard; less expensive than Anderson and Marvin, but so far I'm very happy with them.

If you are looking to keep the "period" look, then I say no. My place is from 1916 & had a gross 1980's reno. I ripped out all the ugly vinyl floor & cheap Sears sink & went with a black hex floor, white subway, dark grey grout on both. Toilet & tub were original, but I got an old "Standard" wall mount sink with chrome legs & towel bars & an antique medicine chest, light fixtures & glass shelving & towel bar off Ebay. My total job...about $5k. Help my tile guy is my neighbor, but those 10, 15, 20k bathrooms were out of the question.

Oh wow, it looks fantastic! The black looks so striking against the white, not too sharp at all. Congratulations on the house, you must be very excited to move in. :)