If you prefer for something sophisticated, this is the right design. It is a dark radiator cover. You can place plants around to make it more lively.
This is a rustic design you could do. Try a panel styled cover for your radiator. It can be a nice hallway decoration as well.
If you have a long hallway like this, you can cover your radiators like this. Use wooden planks to cover your radiator. It can also serve as your window seat and shelf.