I would hesitate before trying to permanently change the brick color. Paint adds considerable maintenance over time as opposed to the current maintenance-free surface, and I don't think that mortor wash or German smear is well suited to your home's architecture. I anticipate that it will be a look that becomes dated, sort of the avocado appliances look of home exteriors, but much more difficult to fix in 5 or 10 or 15 years than avocado appliances since it's a permanent application. Replace the front walk and steps with ones that are wider and of more appealing material. Put a generous landing at the bottom. Look at Doug's sketched columns, thicker and fewer to frame the porch; plan something similar. Change color on shutters, columns, garage doors, and gable ends to something that works better with the brick, perhaps sage or a light gray, and if there is the budget, change the style of the garage doors. Since the front door is recessed, consider giving it a color that will make it visible. Is there good light for the front porch at night and if not, would adding a light that also is ornamental help? Redoing the landscape will soften the brick if it is done well. I would do all that first and live with it for a while before changing the brick to something that you may regret in a few years.

Your brick looks very nice and classic. I see what you mean about the mortar being yellow, but it only looks like that up close. From a distance, I think your white trim is classic and goes well. A green/gray paint would compliment the red brick.

Also try the paint samples near the hardwood floors. It's just as important for the color to coordinate with the floors as it is the fireplace. Paint a sample of the Gentle Cream, Muslin, and the Navajo White on the edge of a large white poster board. Then you can prop it up against the fireplace brick, your white moldings, the hardwood floors, and your rug/furniture. The white space around the colors will help you better visualize what it will look like without the reflection and contrast of your current wall color. It appears that any of those colors would work.

" She advised the German schmear (but probably didn’t know who was doing it) lol. I haven’t updated her yet 😬😬😬" Well. Everyone sees things differently. Just above, Beth posted a couple of stand alone fireplaces, schmeared. The pics with the accent chairs tucked near the hearth. The fire is alone. Flanked by windows in one pic, by wall and a sconce in the other. You say okay, big deal so what? But it IS a big deal. Alone.......IS very different than what you have done ( flank w/built in ) Everything exists in a context. Even schmeared to the MAX ? You have ( jmho ) married a horse to a chicken. You spent a lot on a built in, planked the back of the built in. You will add books, or display treasures, photo's .......etc. Yes? It's still going to feel wrong, Me? I'd say oh well, let's quit while we are ahead. Put the horse with a suitable pony, instead of a chicken, at least. That's why drywall, and minimal amount of brick exposed would be better. Better Yet? Drywall, and a new solid surface, or tile area to meet code and address the raised hearth. ( best case would have been to remove it and infill with a solid surface flush.) You've quite accidentally made two focal points, and neither can dominate . They are fighting one another for attention. .............and that is exactly what is bothering you. Best case is drywall and some new solid surface. Second best drywall and paint . Third best is forget the schmear effort, and get a couple of gallons of white paint: ) You need opacity. Yup........opacity. (Apologies to the very talented/wise Beth up there !! ) Remember........just because you can find it on the internet...........? Doesn't make it great. Like below : ( Imagine instead, lovely window views right to the floor. in this pic.. That fire begs for no competition whatsoever, let alone cabinetry, books, photo's and doo dads Design always begs one to edit ideas or you wind up with "odd couples".