Cool mcm house. Do you like mcm? I would remove the plastic shudders, paint all the trim white, and an aqua door. That is me guessing that the brick is slightly pink (based on the daylight photo). Use white board and batten on the addition not horizontal clapboard.

Good landscaping would really make a difference.

I would match the color of the brick for the addition, so it doesnt call attention to it being an add on. I also agree, nicer landscape would make a big difference.

Agree with removing the shutters, matching the brick color (or slightly darker) for the extension (and the garage door and the downspouts where against brick/siding), removing the tall shrubs near the house and trimming the rest, adding drifts of varied plants in deeper beds that create long, gently curving lines, within which the house rests as a sculptural object. Soft, creamy white that relates to the brick (not bright white) for all trim, including the broad horizontal band above the windows. (Can't tell from the photo whether that is actually the same color now or not.) I personally like what looks like a black door on this side and would do black on the garage side too. Love your Spanish moss!

Depends on if you want to highlight the extension, or try to blend it? I'm a fan of rich dark grays, like an Iron Ore always matches well with brick colors. Otherwise you could blend it with a matching brick color.