I agree with divadeva. More lights. If you can add pot lights do it. If they're already there add task lighting and up the wattage on the bulbs on the pot lights (replace with LED and you can make them brighter because the wattage on LED is lower for brighter light). If you have all of that add decorative lighting. If ventilation is an issue find a way to move the air around or add air filtration. Maybe the HVAC is deficient. Maybe you can add a HEPA filter instead of the standard one that comes with the unit. Call an HVAC specialist to see if there is a way to boost air flow in the room.

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!

A good tile installer that knows what he is doing, can easily remove that single piece of tile.... carefully replace it with another one. Do you have another extra pieces of the same tile? Do you know what brand and color the existing grout is? That will be more of the issue trying to get the grout match to match up or the finding the same tile (in the same dye lot) if you need to buy another tile. Did the heat cause the break or did a pan bang into the glass? Consider installing a heat resistant Lumicor or 3 Form panel behind the stove. Any flat material that can be sandwiched between two resin panels. 1). Crushed glass. 2). Fabric. 3). Fabric. 4). Fabric.

This reminds me of my kitchen in Hyderbad, India. As others said, go with open shelves. Both wood (contrast) and stainless (brightness) would work well for upper shelves. I would also do shelves in the lower cabinets. If you want to minimize cleaning, add heavy, easily washable curtains to the lower shelves. You can add some battery operated lighting so you can see into those darker spaces. As for the walls, I would use a white subway tile and go as high on the wall as you can afford. The glaze will reflect more light and the surface will be relatively able to keep clean. Paint the other walls in a high-quality white paint (use a ceramic one if you can find it, as they are a lot more durable). Keep the appliances to a minimum. Kitchen gadgets might be handy, but lost of them will make the space seem small. For the ones you do buy, go with white or stainless steel. Finally, hang pots, pans and utensils on the walls to free shelf space and get them off the counter. Make sure what you use frequently is within easy reach, while "occasional" tools can be higher up, where you might need a stool to reach them.