I would do a colorful runner and maybe change the lighting fixture but I actually like it I think it goes

I dont think you have to fill this hall way with things

It's unfortunate but unless you can move the thermostat I would just add a rug and call it a day.

Actually I would also paint the intake vent the color of your wall to hide it....there is probably biege spray paint you can buy

I did this to one of my vents when I painted the room a dark green it really helped camouflage

In a small utilitarian space like a hallway, I think the littlest details can make a difference…so I’d paint the air register to match the wall, making sure it fit flat to the wall, and I’d unify the door hinges, strike plates, knobs so they all matched. And if the light is staying, I’d use that metal color as the guide. I’d also paint the back plate of the thermostat the same as the wall, and add a few pieces of art. Hallways are good places to push the boundaries on art, if you’ve loved a piece but weren’t sure it would look good elsewhere, because you’re not competing against anything else, and it’s not in your line of sight the majority of time you’re at home