I like the MCM vibe of the brick. I don't like the stone with it. I would do a wide clapboard in place of the stone and paint it gray. Do a gray roof as well. Improve the landscaping including some trees out it the yard.

Agree with houssan to have charcoal roof and trims--medium charcoal to match grout color. (Do you have an image of the new addition? Too much contrast might highlight the addition rather than the appealing long lines of the house.).

Replace the stone over garage with whatever color siding you use on new addition. Start a Houzz Ideabook for "MCM landscaping" There's so much you could do in front with foundation plants and hardscaping that will provide a contrast to the orange brick color that bothers you. I happen to like it, just not with current roof and landscaping.

Example of excellent MCM landscaping and hardscaping:

Mid-Century Front Landscape - Fox Point, WI · More Info

Taupe trim and garage door. Take a closer look. If you have a very large second story adddition going up then taupe might be more harmonious with the brick and your wide driveway.

Here's a ranch in charcoal brown. Taupe, though, is a good way to go. Do note the landscaping in all the photos.

Taupe garage door and trims, light brown roof. Take a closer look:

Mid-Century Front Walk - Wauwatosa · More Info

Focus people! With all that construction, landscaping is not on the table for some time! Before I read what you posted I was looking at the home amazed at the large ranch style it is. It's an amazing home. It doesn't appear the stone near the front door and over that garage match? Is that just the shadows? Maybe it's the brown garage door??? It blends very nicely what's by the front door. Can you get more of that for the second story? My first inclination would be brown roof and trim.

The brick is amazing… I hope the addition is sensitive…

This is the image of the proposed addition. We are still working on prettying it up with window shaping, elevations etc.

So the designer hates the existing house.

Oh, dear. Sorry, but you don't drop a colonial-style addition with a different roof pitch & dormers no less on top of an MCM ranch house!! I hate to say it's terrible, but it is. I hope some architects will volunteer a sketch to help guide you to a better decision.

Your home has horizontal lines (Praire Style Design) like you see below on this before and after ranch house remodel.. Those horizontal lines and roof pitch should be duplicated on the second floor so it doesn't look like a mistake

I'm no architect but I changed the roof pitch and eliminated the dormers to illustrate what I'm talking about. The window placement is all wrong but this at least gets the concept across.

I can’t comment on your addition, but just wanted to commend you for not painting/staining/limewashing your masonry. It’s Roman brick, very desirable.

https://midmod-midwest.com/mid-century-brick/

That brick is wonderful! Very Frank Lloyd Wright and in that vein, I'd keep to earthy colors. Have you seen SW Napery for the trim?

I agree. I believe he just showed us that image for elevations but we’d need it to be a different roof on the addition

A question: why are you putting a huge addition on what's already a large house? Not my business, but reading Beverly's comment below about the prairie style of the house made me wonder if you've really thought through that idea. Your house is very attractive as it is. Everyone has given you some wonderful suggestions on how to enhance your exterior, but a huge second story in a style that doesn't reflect the great style of your house will ruin the house. Seriously.

Have you had your house checked out, by a structural engineer or other capable contractor, to make sure your foundation, can take the weight, of a huge addition on top of it. Some houses, cannot take that weight. I have to admit, hope your addition doesnt look like that one in your picture.

I agree. I believe he just showed us that image for elevations but we’d need it to be a different roof on the addition

You agree with who/what?

Elevations show what will be built, including the roof. What you see is what you get.

I'll suggest you take a step back and ask for a review of the addition plans here on Houzz, and find a designer to consult on the exterior.

PPF your renderings are fabulous. I hope the OP chooses one of them!!

There are a number of problems with painting mid-century brick, including aesthetics, technical issues and maintenance headaches.

Have you considered using the garage for the addition you want? There is a ton of room in a two care garage and it's free. Thinking black for all the trim and doing something great with the face of the garage and landscaping.

Building another garage on the property, in like style, would eliminate the second story. I've seen it done and the house winds up looking like a split level. Nothing wrong with a split, but your house is unique in its design. Don't go up.

I like the Roman brick. I'd prob go dark. urbane bronze, Iron Ore.

You get something that looks like these

bring in some wood tones and mcm style front door/lighting

The biggest change and updo will be the landscaping. spend the money for a pro landscape designer that has a feel for mcm. THAT will bring everything to fruition.

imagine this yard

finished to look something like this. (this is a desert landscape, so you'll have to adjust)

notice the garage door, the walkway, hardscape, address numbers.

to compliment the oragne, work in autumn colors in the plantings, natural wood, copper accents,

green grass, hardscape path,

simple but neat and clean

those retro fit white vinyl windows do not go w/the home. i'd do bronze, something like these. notice the landscaping too. and instead of the rock in the gable,

and, a more modern garage door

similar roman brick homes. look at the windows

bronze, not white. period appropriate

need more brick?

https://retrorenovation.com/2015/04/13/where-buy-roman-brick/

I' not suggesting you paint the brick, but it has been done here w/soft black color. I like it

https://www.dwell.com/photos/exterior/building-type--house/siding-material--brick/building-type--mid-century

Questions - What issue you are solving for? Do you have space in the back?
It may be more cost effective to expand to the back yard than adding a 2nd story. And costs aside, if you do decide to add a 2nd story, have expert help to ensure it connects well with your current your lovely home. Best of luck.

Are you all attempting to design the addition yourselves, or are you paying someone for this work? I think you need to find a designer/architect that understands the importance of unifying the old and the new in a way that respects the home’s history. There is a night and day difference between the renderings PPF posted — which would result in a stately, unified home that maintains similar lines and looks intentional— compared to the elevation you posted earlier, which wouldn’t accomplish any of those things.