What a nice space to work with, steveholt! You might take your cue from a great hanging light, maybe borrow its finish for a gallery wall going up the stairs. Some ideas from a couple of recent ideabooks:
https://www.houzz.com/magazine/weekend-decorating-8-ideas-for-lighting-your-entry-stsetivw-vs~377891
https://www.houzz.com/magazine/keys-to-a-stylish-entry-stsetivw-vs~320703

Can you take the carpet off of the stairs? That would make a huge difference.

Paint the whole banister white, or at least the vertical balusters, and perhaps leave the handrail part of the banister natural (or, go black for a pop. Black would go well with that small piece of furniture in the nook of the staircase)

Not sure of your decorating style, but framed photos (black frames and black and white prints) or plates on the wall would be a nice addition.

Consider adding an area rug for color and pattern, artwork for more color, a bench on the side wall with a mirror above, and some decorative lighting.

I'd begin with removing the carpet on the stairs as well as the doormat. Paint the stair treads white as well as the spindles, and paint the railing black. If you simply must have carpeting on the stairs, have a runner installed - and consider a striped carpet or even a bound seagrass or jute that will emphasize the run up the stairs.

Consider painting wide vertical stripes on your walls - perhaps in the same color but in a gloss, or in a slightly lighter or darker shade.

Remove the spindly table in the corner of the staircase and replace with an elegant round pedestal table in a dark wood - In the center, place a large glass vase where you can display fresh flowers.

Where kitty and her rug are, place an upholstered armless settee - and above, mount an ornate round mirror. Leave the tile floors bare.

hi
It will make a great difference to put synthetic parquet sheets on the stair case,paint the balustrade white the top rail black and paint the walls in stripes of white and silver or light blue and silver horizontal lines of not less than 40 cm of height will widen the space

The space definitely needs more natural light. How about a new front door with glass (obscure glass if privacy is a concern). And is there any chance of eliminating the coat closet (do you have a mudroom or other place to hang coats)? The space right now appears really constricting and uncomfortable as you walk into the foyer so anything that can be done to open it up / give it more light would be great. That's what we did to the foyer in this photo and it made a huge difference.

get rid of the ugly tile in the entrance, it's basic home depot stuff. A linoleum checker pattern is durable and cheaper than what you've got to maintain . Change up the stair railing ballusters and bannister. It's all very basic home depot upgrade and not in keeping with the home's potential and origins. Look at 'recyclingthepast.com' for the real deal. The door is sad. Lose the partition wall on the left and use that space for window lights from floor to celing next to the door, which should be swapped out for a door with lights at least fully on the upper half. Take out the coat closet and create a space with hangars and built in shelving on the floor for shoes and umbrellas. use the free wall space to add more window lights, perhaps even small narrow windows that actually open to help bring in a cross breeze or fresh air.

How about bringing some life to your walls? A bright color, like green or yellow would be welcoming. Or, you could go bold with a deep blue or red. Also, like others have said, new light fixtures would brighten up the space. Hanging up artwork and photographs in the stairwell is a good way to add personality, too.

i fully agree with simplysteph and bepsf - those three brown/greyish colors clash a bit in my opinion and the hint with the paint is good as well: have a look at the pics i altered, including one pic from the link sheila posted - it adds a bit of graphic and excitement to the room.

otherwise: maybe some black and white framed monochrome photographs, a small and long mirror on top of a half-moon console table (on the right on your way ou)t should work

paint, paint, paint! it's amazing what it will do. I would use a semi gloss to reflect light more and brighten. i'm not sure of your decorating style, but i think a light blue or green would be very inviting. just make sure it has a warm undertone as opposed to a cool so it doesn't make the tile look dirty. paint the closet door the same color as the walls...it will disappear. i think i see another door- paint that one, too. A sizeable persian rug at the entry would look beautiful. Something neutral, but with pattern.

I agree with the advice you have gotten so far, especially replacing the front door with one with glass. The actual entrance does seem very confining. Is this a two-story area, or is there a typical ceiling height above this? If it's two-story, add a big, bright light fixture. If it isn't, perhaps add light sconces on either side of a mirror/console; also, add mouldings if they aren't there. Replace that slab closet door - it screams "builder" - or at the very least paint it into the wall. I am assuming that you don't want to go to the work/expense of replacing the tile (but if you do, either replace with wood or a smaller tile set on the diagonal), so find a larger oriental runner to use here which will cover more of the tile and add color/interest. I think taking the carpet off the stairs would be nice, but be advised that there probably isn't nice woodwork under it! In lieu of this, use a brighter paint color - a foyer is a great place to use a dramatic paint color that you wouldn't use elsewhere! Take a cue from the accent colors in adjacent rooms - or if you really don't have any, the sky's the limit!

Not knowing your color preferences, I will tell you what I would do if it were mine. First I would paint the walls in a sage green, the wall going up the stairs would be sage all the way around the front door to the corner of the closet, the other walls would be a shade or two darker. I am guessing you are standing in the doorway taking the picture so the room is not big. Over in the nook where kitty is, place a bench, either built in or free standing with a pretty cushion on it, in a green plaid or floral. Put family pictures above it. Over the table there add a pretty mirror for last minute touch ups. Create a gallery going up the stairs of family picture or of things that interest you. I would use wood frames to help draw your eye up and tie in with the bannister. Replace the dark rug in front of the door with something to go with the walls. As for the closet door, how about a louvered door painted out to match the trim which I would leave white, since it is already. These are easy changes that you can do mostly by yourself, not having to hire a contractor and tear things all up. Replacing the front door would be nice if it will fit into the budget. If you really like the color you already have, how about painting the lower part a shade or two darker of the same color and go from there (or the upper stair wall, two shades lighter all the way around the door to the corner of the closet). I hope you will share pictures when your finished. Have fun.

I like a lot of the ideas you've read already. New door with a window in it - you could go formal or more cottage-style depending on your taste. Paint the walls a light color - maybe a soft aqua or lavender. Some kind of art on the walls, different sizes and shapes of frames will create interest. Something larger in the corner to replace the sweet little table you have, and a bench to help hide the kitty spot. I would also remove the carpeting on the stairs and paint the stair rails. If you're really adventurous you could paint the rail black and each spindle a bright color!

Color! Paint those walls. I would suggest a wheat/golden tone.

You can use bolder colors (yellow, red, orange or lime green. Changing the floor color would be a tremendous help as well (white or neutral). The carpet on the stairs need to go ---- use wood or non-slip tiles. Showcase the foyer, don't use it as a non-existing room.