They should be about 1/4-1/3 the height of the door, so definitely the 24" light could be even taller. Keep in mind that when you look from the street the lights will appear smaller.

The shiny brass would be appropriate on a more formal less country style home. However, the likely reason you do not see polished brass exterior lanterns on the outside of homes is because the metal pits and turns colors over time. To keep them bright and shiny, they have to be removed and polished. Even the lacquered brass will turn over time and have to be sent out for polishing.

We recommend choosing the size of outdoor wall lights based on the height of the door that they will illuminate. It sounds like you want to use two lights, one on each side, so measure the height of the door in inches and then look for ones that are 1/4 the height of the door. Let's say your door is 7 feet high, or 84 inches high. 1/4 of 84 is 21, so your thought about 24" lights is on track (it's OK to go a little larger since these lights will also be viewed from afar). If you haven't chosen your lights yet, we can help you with that too! I filtered our selection of outdoor wall lights to show the ones that range from 21" to 24" tall. Let me know if you would like me to pick out some recommendations from our selection!

@cd773333 I need the lights in about 4 weeks. @katinparadise I like the one you suggested but too expensive for my budget. They do have the one I like in bronze color. Do you think it looks nice with bronze. I do have dark bronze exterior window frame. Should I consider antique bronze. I just wasn't sure if the light bronze would work well against my dark bronze window frame. https://www.build.com/progress-lighting-p560021/s1286790?uid=3057940