Usually, the larger the radiator the higher the BTU. However, you could also select a radiator that has a second panel or layer. This second layer can significantly increase the amount of heat given whilst maintaining the stylish look of the radiator.
Crisp, clean, white makes small spaces seem bigger and brighter. I love how even the radiator is clean and white. Pair this with an awesome book shelve and it provides character to an otherwise boring room!