Fix your roof too, before the rains... Sorry, just saw the tarp.

If you take down the rock, can you install a big window in that space? A closeup of the garage door would be good so that we can suggest a way to paint and make it look more attractive. One way to "lose" it is to paint the whole house including the garage door a darker, more interesting color. The entryway, is dark and we cannot make out the details. More pics? Is it possible to install more modern windows and a new front door? They always make a difference. The roses are nice but you may wish to add more plants to soften the concrete edge of the driveway. Likewise with the planter box up against the house.

How about boxing in the area above the stone? Lateral strips of wood spaced widely enough to allow the vent to work..strips can be 2-4 inches or wider and painted to match the rock or the house..line up with the stone so it looks like part of it

Maybe box in the tops of the stone planters to match ...and tie it all together

Another easy fix would be to cover the vent with a frame and lattice and paint to match the house

Thanks for all of the comments. The photo I uploaded is 2 years old (the roof has been repaired). I will upload some current photos. My husband wants to 86 the vent and take the stone all the way to the roof. I would like to add a mid-century window, but I'm not sure how it will look.

Here are some better photos of the house. We want to keep the 50's ranch-style character of the home. One thought is to take some of the stone from the planter and extend the stone wall over the vent to the roof. I want to add windows to the same wall, but afraid that it will still look odd.

you are concentrating on the wrong thing - garage does not look bad. you really, really need landscaping - plants, shrubs and trees.

Yes, I know that. One project at a time.

Out here in Southern California, we are going through a major drought. Water rationing and so on. Can't plant for now. It is what it is.

I like Andrea's suggestion about the two windows. If they were high and on either side of the stone/vent area they would let light in to the garage without having to be covered. Is the garage more comfortable with a vent? It's good to have a vent in a garage...just wondering. You mentioned that you plan to landscape. What if you plant a smallish multi-trunked tree in front of the stone and lower shrubs under the new windows and another tree on either corner of the garage wall. It would break up the square space and cover up most of what you don't like about it now. The existing stone planters would be too small for my suggestion, though.
I'm in Southern California, too and I'm glad you ripped out your water guzzling lawn! I am negotiating with my HOA right now about this issue. If you plan to add shrubs and trees, fall is a better time to do it than spring, as you probably know. If we do get any rain it will happen in the winter and your new landscaping would benefit greatly.
That's a good sized front yard! You could even put a low wall halfway out to the street and pave much of that area for a front yard patio. Lots of possibility. Have fun!

I also like Andrea's suggestion about the two windows. We don't use the vent, we had to board it up due to rodents. I love the suggestion about the trees and landscaping to soften up the boxiness.

I don't want to add any more pavement, because our paved driveway is pretty massive. Thank you for appreciating my dead lawn. Half of the lawns on my street are dead because of the drought. The plan is to add synthetic grass, surrounded by a drought tolerant border. Synthetic grass is not my first choice, but I have a young boy who plays baseball and he needs to be able to run around out there. Thank you everyone for your comments!

Per the great suggestions (without landscaping). I think the windows will look nice.

If the vent is not in use and you have extra stone why not continue up to the roof?