Beautiful clean modern kitchen! You have a great opportunity to put your personal stamp on the space with a unique backsplash. As you've heard already there are some different approaches. I'd probably place the backsplash up to the wall cabinets and up to the base of the hood. Then continue the backsplash at the same height (18"?) behind the sink. Then place an inspiring colorful picture above the sink to break up the wall. Here's a picture with pendants that aren't too obtrusive. Having multiple levels of lighting at different lumens makes a more inviting feel to the space. I couldn't decipher your flooring, but you may also want to consider adding some nature elements like a type of wood flooring, wood stools, etc. Good luck! If you need software to plan out materials check out our Home Designer software: http://www.homedesignersoftware.com/

Splashbacks are all about protecting the walls behind worktops, hobs and sinks from splashes. A splashback can make a small kitchen feel larger, and brighten any space. You can Choose splashbacks from plain mirror, antiqued finishes or colored versions. Pick good looking but easy care splashbacks. You can match splashbacks and worktops. You can also choose Image on glass NZ service, it will freshen your kitchen up with quirky.

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.

The number you need for adequate lighting is dependant on the light fitting, its brightness and the angle the light will cover. The physical size of the fittings will also affect the number that looks best. Two very small fittings may give adequate light but look lost, while three larger ones could seem crowded. You may even find some very small fittings that work well as a group of six. Take into account the width of the surface as well as the length so you can ensure it is all well lit. You may be able to change the brightness of the lamp in the fittings to give a good work light in the number of fittings that look best. Avoid creating strong bright/dark contrast areas on a work surface. More overlapping less-bright light is better than few brighter ones that leave dark patches between them. Also consider whether there are other elements in the space that the group of light fittings could relate to, whether window mullions, cupboard doors, seating etc. If something else is creating a strong rhythm, decide whether you want to echo, or offset that or have the lighting as a background element that doesn't have a strong relationship to it.