80" was what our electrician's suggested for our two sconces. But my wife and I are both under 5'5" so we settled on lower - I think it was around 72" (originally we had 66"). With LED bulbs they are very bright and we'll have a dimmer installed so we can adjust the brightness. Tough in a guest bath if you have guests of varying heights using it.

We'll need more information. Would you want to transform the current porch area into an entry? What is on the wall near where the red bush sits in your picture - could that be used for entry space? Do you want to add on an entry? So many options... To help us, please post inside pics, pics of the inside/outside where you'd like the entry to be placed, and dimensions of the area.

We have a Regency HZ40E direct vent gas fireplace, and a little wood mantel similar to yours. This was the minimum height above the fireplace that the mantel could be installed -- 48" off the floor (8-foot ceiling); 16" from top of trim to bottom of the mantel. I had the fireplace going for about 30 min this morning, at least an hour ago, and the mantel is still warm. Your entire fireplace/mantel combo might better be placed lower, but I'm really not convinced that your mantel itself is too far away from the fireplace.

I have three 11" Blade LED Wall Sconces two of which are between windows in a room with 8' ceilings. Bottoms of sconces are 65" from the floor and centers of the 4" electrical boxes to which the sconces are attached are 67" from the floor. Lowering the electrical boxes by 4" (to 63") would have made them too low, I believe.