mirror 1/3 the length of the wall but hung in the center.. what size do you want the table? length? height? depth? i am sure you can find one and if not then hang a narrow shelf instead with some hooks behind the door for your bang, etc.... see link for info on entryway mirrors.. https://www.ovalandroundmirrors.com/finding-the-perfect-foyer-mirror/ also type in narrow long entryway table.. see link https://www.google.com/search?q=narrow+entryway+table&source=lnms&tbm=shop&sa=X&ved=0ahUKEwjX9ej_vN3fAhXdwMQHHbXrBQUQ_AUIDigB&biw=1536&bih=676

the table is not a must but a narrow shelf to put something decorative if you want would be good.. size is what you think is a good depth that would not get in the way of opening the door opposite the wall and the front door.. you asked for a way to dress it up and these are some.. it really is all personal preference.. and the rug should be something that matches the room beyond or a pretty one that makes you happy and is non slip.. when you open the door what is left of the wall space? take that measurement and get a shelf / mirror that is half that so when / if the door is opened there is no damage.. you do not even need a mirror you can hang some artwork instead... i posted mirror since you asked about mirror.. artwork on the long wall and beside the door opposite to enliven the space.. find something that brings you JOY.. ;-)

A narrow entry table and a mirror would look great in that space. I don't think a rug is a must (in fact, I'm not sure I would do a rug). Optionally, you could add some dimension to your wall through board & batten (depending on the rest of the style of the house) or wallpaper as Besty suggested. If you want to keep that bench, I think you could, but would just add something above the bench to fill out the space more, like in the second photo. Be sure to post some after photos! We can't wait to see what you decide on!

I really don't think the floor is ugly.. and sometimes folks cannot or will not change floor.. saying ugly floor is kind of insulting.. if you yourself do not like the floor and cannot update it then a solid colored rug would be best - maybe a runner down the middle from the door to the wood floor.. keep everything in the same color shades.. a mirror is only needed if you will used and / or to open the space or maybe some favorite artwork instead.. there is no hard and fast rule for this entryway especially as you do not used it all the time.. enjoy the adventure of fixing it up and do what makes you happy!

Rug, new overhead pendant or semi flush light. Don’t try to squeeze in seating. Hooks / artwork - keep it open and clutter free

Something like this for the entry, with a rug that will cover most of the floor maybe:

And if you are looking at budget friend or DIY table, your hardware store should have the spindles for the legs and find a piece of wood similar for the top. You can stain and distress for this look.

And inspiration that coordinates for your living room

A mirror and rug are both good ideas. I would remove furniture though because it seems the space is a bit cramped/narrow with it.

thin table. Stools underneath -add caster wheels for easy movement.

Large mirror expands the feeling of the space

Extra wall hooks for guest totes, hats if no space in coat closet

I would remove the padded bench and just use a large mirror or painting on the wall. Open and uncluttered. Some of the examples shown are lovely, but they do not have the same space or dimensions as your area.