How much larger is the footprint of this room going to be? Do you have a floor plan of the current set up for comparison? There are too many openings, and I don't understand connecting the mudroom to the dining room at all, especially with such a huge French door.

What the architect labeled the mudroom is the dinette. The room will be doubled in size. The point of those large French doors is so that when we have family over we can have a large open area

Is there a patio or place for one outside the windows?

Instead of a picture windows, you might consider using only French doors and French door length sidelights to which you can add gathered curtains affixed to the doors at both top and bottom.

Alternately, choose the doors with built in blinds and you will not need room darkening curtains.

The picture window is already there... I don’t need room darkening curtains, just think they are pretty and help finish off the room...

Could we get photos of the room from a couple different angles?

The room isn’t built yet:) I can give additional pictures of the current room that is half the size, but it is completely empty now as construction should be beginning. I kind of jumped the gun by asking about paint colors and curtains, just want to pick out what I can without pressure. We are planning on doing a dark brown wood-look vinyl floor for now and the furniture is dark, so my biggest concern is keeping things light

So, is that dashed line in the middle the former wall?

Yes:)

Don't know what style windows you're considering, but I think those two windows would be enough if they were tall and nearly to the floor. Then you could eliminate that big window on the east side of your drawing and put the buffet there, putting just one large French door in the middle of the south wall, opening into the larger room south of the dining room to save door-swing/floor space in the dining room. All dependent on whether or not I'm reading the plan correctly.