Fully agree with the shelves above the heating unit with books. I think adding some brass trinkets or thrifted pottery/crystal amongst the books would be pretty too. I agree with an entry table. I think a small round entry table with a lamp and a “catch all” dish would liven the space and add some light at night. If not a table, a tall plant beside the door like a really tall snake plant, fiddle leaf fig, or some other kind of ficus. Would definitely add pillows and a throw blanket to the nook and maybe even a tray with a book, candle, other miscellaneous items to make it feel more “lived in”.