Rinnai offers ductless direct vent wall furnaces. They sleek in design as to not take up much space, very efficient warmth made in different sizes. They have flexible installation options and maybe controlled by a wall thermostat.
Sunheat makes electric infrared space heaters. The original 1500 heater is made here in the USA with solid wood tops. The copper heat exchanger has more than 4 times the copper found in other infrared heaters which means more free heat.