Embrace the arches and keep it light, but add some contrast. Paint every wall with an arch in it fresh white, all ceilings too. Paint the adjecent walls a soft color. For example; when you keep the kitchen tile, you could paint the walls above it a soft pink or mauve. I see three open areas, so you could divide those with three soft colors and white inbetween. Keep most lights simple and functional, uplights will enhance the arches, glass pendants will add warmth. And I think a soft olive or sage green is a great color for a living room.

I'm not against colorful homes. There's bright, and then there's too bright. I wouldn't go with persimmon for the whole house. The photo you provided has lots of white trim which offsets the orange, but your house doesn't have that much trim (unless you were planning on adding some, which I think would look good no matter what color you ultimately choose, but even so, I wouldn't go with persimmon for the whole house, as it's still too bright). To repeat what @nwduck said, the other homes in the neighborhood don't appear to all be done in the bright colors, and so yours would stand out too too much. I like @deco's idea of the bright door, if you really love a bright color. For the rest of the house, any more subdued color would be fine, along with additional trim around the windows, and assuming that your siding color coordinates with your roofing color.

Unfortunately all your options require custom work: It looks like you need an 18" corner cabinet. You will have to modify the last wall cabinet on the left. As I am eyeballing it, you should be able to cut the last cabinet in the middle and then shorten the left section to fit the space of the wall next to the door trim. It's an option that makes the area looks symmetric. Or you can install shelves over the sink. I would not recommend it because it will take the looks away. And the last option will be to remove the last cabinet, shorten it so it fits over the sink and install a single cabinet where the double one was. This will leave a triangle space behind the corner where the two cabinets will meet. You can block the space under it. Hope this helps!

I have used both with good results. The main difference between Quartz and Granite are 1) price, 2) colour range. Granite generally works out cheaper, because you can buy the exact quantity you require. Quartz comes in large slabs of specific sizes- standard size being roughly 10'-0" x 4'6", so there tends to be more wastage if you don't plan the cutting well. But Quartz is pretty and comes in a wide range of colours and can be re-buffed at a later date. Quartz also comes in various thicknesses- the most commonly used being .75" to about 1.25". And especially when you use dark wood cabinets in a kitchen or bathroom, beige and white counter tops work very well. Some people go even with coloured counter tops like blue, orange, yellow. Natural stone in light colours tend to be porous and stain easily, so I prefer to go with pure black which is safe.