I just checked the custom built-ins in this house and they are all 11 1/2" deep. I have decades of books and all fit neatly, I wouldn't want them any more shallow if I had a choice (understanding that few homes are perfect :)) But back to the cable box, I wouldn't design something permanent around them, I'd let one extend into the room first before tearing into a wall for depth. I don't know your company, but in the last year I've replaced (or added in one room, hadn't planned originally to be watching TV in that space) three cable boxes...the oldest in my office is a whopping 13" deep, more than 17" wide (and silver which doesn't go with my décor). The other two, all three of them Comcast, only 7x9". And a discreet black.

If you have a rainscreen, I would caulk it. You dont want water rolling off the glass behind your trim and siding, even with a rainscreen. That is an interesting detail with the wood trim on top of the cap flashing though. Is the painted brown piece some kind of flashing? If the sill pan drains to the top of that flashing, you probably shouldnt caulk the piece of wood sitting on top, as it could trap water. I would caulk the horizontal gaps below the brown flashing though as they look more likely to admit water than let it out.

Since the stone and brick are dissimilar materials I would expect the mortar at the top of the intel to be raked back and sealant installed. Flashing behind the lintel should direct water from the wall cavity to weep holes or tubes at that location. I'm assuming this is a brick cavity wall rather than a solid double-wythe brick wall. You need to clarify that issue since it would change the detailing of the lintel; we can't see whats behind the face brick or guess how old it is. It can't hurt to treat the broken lintel as if it were still good for now. Obviously sealing the crack would help prevent water from getting behind the top of the window. The location of the crack directly below the end of a gutter is suspicious. It's possible water has been overflowing from the gutter down the face of the wall and getting behind the lintel and freezing, assuming, of course, you are in a northern climate.

@decoenthusiaste LOL! I regretted the 'modern farmhouse' when I wrote it. I think I mean a monochrome look, darker overall, with siding, trim and fascia all one color. I am just not into the white highlighter outline look so many are doing. Want to be ahead of the trend and stand out. However, I am so afraid to get it 'wrong.' We did choose a roof color that pulls all the brick colors together. It's an overall medium to darker gray, with hints of warmth and black through. We would ideally like to avoid coating the brick. We would consider after, if it looks bad. We would really like to keep it and roll with it. The garage doors will be converted to one larger door, but yes, there is brick between, with a strip of hideous siding above currently. All to be redone. Unfortunately, we are headed into winter and the siding color needs to be selected this week, or we push to next year...and we just don't want to do that.