I wouldn't drywall over the window. Take a look at the options for recycled brick, they may match better than you think.

When you're doing lighting in a kitchen it's a good idea to have good directed light over the main tasks areas, cooking, dishwashing, food prep. You could achieve this with downlights directed at those areas, or track lighting where you can direct/angle each of the lights on the track. Re the pendant over sink area, would need to be at a height that ensures safety - water & electricity, not a good combo. There may be some NZ standards that you can refer to, to get the correct info.

I'm not sure how easy/cheap professional systems are to install. But it might be easier to look at the IFTTT app which works with "smart things" by samsung and many other samsung products, belkins we-mo, and even fit bit.

Have you tried a custom lighting specialist?