Anything with legs would fit over your floor vents. The bench that you described would work. A console table would work...it is open underneath. In the corner near the front door (opposite corner from small vent) but a large upright plant...real or artificial. Then a round colorful rug in the space in front of your door.

I think the space looks nice as it is. I wouldn't try to force anything in there. Maybe replace the current light with a chandelier and add a circular rug.

A beautiful circular rug would really make the entryway look beautiful and inviting! The only area I would want to do something with is the area that is beneath the staircase, where the big floor vent is. You could do what others have suggested--place a table that has legs so that you do not block the vent. The bench you mentioned is a little on the small size. You need something a little taller. Here is what I'm talking about:

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The bench is perfect as is your light fixture. I think I'd paint the door in blackboard paint and use chalk to welcome your guests. Add a nice rug. Don't try to do too much. It already looks nice.

Jess--I know about the upper floors being hotter than the lower levels of the house! I live in a 5 level house and I'm on the 4th floor in a bedroom that was converted to a quilting/sewing room. I have a ceiling fan on and it will stay on while we are having this hot weather over the summer. My son has the attic bedroom on the 5th floor and he is using one of the window A/C's that we had at our old house just to keep his room cool!

Choose a knockout rug and coordinate one or two accessories with it. It will be simple and pulled together and welcoming.

I think the space should be a bit more elevated in appearance than just a bench and space for shoes. The console is from Wayfair