You can see how dark the built in/wood work is. The floors are maple so will be left natural once sanded. I also included photos of the staircase, which is another wood type.... worried about too many wood colours in the house and if it will look patch-worky. :/ again, not my furniture so ignore all that :)

Spot repair using polyurethane is problematic since the finish does not 'feather' well. That means the finish does not blend with existing surfaces in a repair area easily. So, what I have successfully done on several occasions is to start with 100 grit paper(I favor a random orbit sander) and get the big problem areas smooth and chip/flake free. Don't worry about defined edges, just get the problem spots.The random orbit sander is much faster than a 1/4 sheet sander. Then switch to 150 grit paper and get the sanded surface smooth. You want to use the same type poly as when you refinished. Use a rag dampened with paint thinner(if you are using oil based poly finish) or water(for water based poly) and remove all the dust/etc. Apply the poly on the sanded area, using only enough to cover the sanded area. For that small area, a paint roller with a thin nap(thicker naps will cause bubbles)---1/4" nap is fine. Now for the blending/feathering. I use a cotton Tshirt as the feathering tool. I use a piece about 12" square or 6" wide and 12" long. I fold it until it makes a ball with a smooth surface. I dip it in poly and begin wiping the edge of the fresh poly in a circular motion, moving outward until the pad is dry. Then move back into the fresh poly and keep up the blending until the entire perimeter is done. You do not need a lot of pressure. And you will find the best method of wiping as you proceed. Since you will need three coats of poly to complete the repair, you will be able to lightly hand sand the perimeter before another coat.

Choosing the wall paint color has always been my last choice to make after I have selected all rugs, furniture, and window treatments.

I recommend waiting until the floor receives it's final coat of finish. Maple has a LONG history of darkening when it ages. Sigh. I hope someone told you that. Anyway, maple is photosensitive. That is to say it gets darker and stronger in colour as it is exposed to sunlight/UV light. And that includes any light source (light from bulbs will take a little longer to turn bright yellow...but it will still happen). Right. Now that you know, you really should wait as much as 6 months before putting down an area rug over newly finished maple. This will allow for two things: 1. You will have a STRONG understanding of how your furniture works with the floors/fireplace and lighting in your space. 2. It allows the floors to darken evenly. If you put down a rug too soon, you will find you have a rug-sized patch of VERY pale maple...surrounded by a strong 'margarine yellow" colour. Even if you work with a water based polyurethane (aka "clear coat") your floor is still going to turn margarine yellow. There is only one way to keep the floors a blonde wood tone: A UV blocker added to the polyurethane. The expensive names in floor refinishing systems have this but the regular (ie. cheap) finishes do not (or not that my research has shown). Loba produces a product called UVProtect which is an additive that prevents as much as 90% of the discolouration that maple is known for. If you wish to avoid the colour change, you will need to speak with your refinsher very, very quickly. Regardless, you will want to wait at least 6 months before throwing down an area rug. Which means you have plenty of time to find something.