The house looks very livable. I love that you have concentrated on creating one nice bath with separate walk in shower and a windowed tub! Since you have already thought of it, I'm going to assume that the attic is for future expansion and cannot be adapted for use as the current "away room." We are also in the process of designing a small house, and we've designated our study as the "away room." Ours will open off the dining room. If you switched the locations of the Study and Bed 1 on the same side, you could put french doors or an extra wide door with etched or decorative glass from the hallway into the right hand corner of the study. This would give you a really long diagonal view through the lounge and out the french doors, and from the lounge through the study to the window at the far end... The study window should be increased in width to match the neighboring window in Bed 1, and it then becomes ripe for a small window seat, either a clip on bay bumping out, or a "built-in" bay using narrow built ins on either side. Or both: build "in" for now, putting file cabinet drawers under the window seat, and angled corner units in for storage, and add the bump out bay later when you know whether your offspring would prefer a really cute desk, or a window seat, or a bed nook. You would, alas, lose the door from Bed 1 into the bath.... but honestly, there are lot of doors into that bathroom already, and that one has substantial collision potential. It might be best to make the single access point that door from the laundry. Either a glass panel set high in the bath room doors or a transome would make it easy to tell when someone is in the loo. Other ideas would be to split the nook under the stairs, so that half the depth opens to the lounge, and the other half to Bed2... with the wall thickness, you probably get close to 600mm or 2' on each side. Add a deep bookcase or other built in, and you're easily at a depth that makes both spaces very tucked in. Lastly, if funds allow a shallow bay window over the kitchen sink would visually expand the kitchen, particularly if you could arrange it so that the counter runs right into the bay.

I would suggest you take out the cabinet that is to the right of the stove and use it elsewhere in the house -- perhaps in the bathroom or dining room with a hutch above it. Then, I would suggest you have someone install a lazy susan cabinet in the corner between the sink counter and the stove, meaning you would move the stove down a bit and have a small cabinet/counter top to the right of the stove. I would suggest you have the cabinets refinished in white and then paint the walls a pastel you like. If you would prefer white walls, then add white-painted crown molding and paint the ceiling a light neutral blue, such as Sherwin Williams Niagara Falls Blue. Then, I would suggest you choose a favorite accent color and use this sparingly in accessories like towels, pot holders, small vases or floral arrangements, and a valence above the triple windows. For a genuine 1940s look, you might have white ceramic square tiles with a rectangular red border installed as a back splash behind and above the stove. If you are replacing counter tops, I would suggest a light color such as white with a beige or light grey vein or striation for some sort of pattern. You might be able to find the same color and design in floor tile OR opt for a wood floor as another poster suggested.

I never love open shelving in a modern kitchen they are dust and grease traps but I would hang horizontal glass front cabinets and paint that wall some awesome color ,run your backsplash up to bottom of window all across. If you have space make the island top larger and paint out the other wall of cabinets to match main ones. The island top could be something much different than the others

Bottom line, a toe kick is to stop you stubbing your toe and get your closer to your worktop counter. If you can fit your foot underneath it in shoes or barefoot while standing at a counter and not stub your toe or hurt your upper foot, you can do it. If you cannot, you will be forced to stand back further at your counter and that will not be comfortable for you in the long run.