Congrats on finding the home you both love!
Lighter walls will work with darker carpets and make it look larger. Depending on what accent colors there may be in the kitchen, you could opt for a lighter version of that accent color, or white or off-white walls.
I've found that using monochrome colors makes a room look larger as well. For example, if the larger pieced furniture is close in color to the walls, ie the sofa, it blends, and you can use accenting colors in lamps,pillows or seat covers.
Depending on your taste, if you like modern looks, a glass topped dining table with maybe chrome or wood base will also make the dining area look larger.
Also, depending on the age of your new home, there may be hardwood floors under the carpet already. My home was built many years ago, when people thought carpeting was nicer, and I have found that all the rooms in my home have hardwood floors underneath the carpet. We've ripped the carpet out of one room, which had some pretty bad scratches on the floor. It just needs to be re-sanded to repair. If you want to check for this, use a screwdriver or knife in one corner of the room and pull back the carpet to check. It IS a pain to take away all the carpet-nailed edging and moldings, but in the end we have nice hardwood floors.