I'd keep the worktops as pale as possiible, quartz is a good choice, maybe with a little silver or grey fleck. Adding another colour with regards tiles is going to be difficult as you've already got a strong accent colour with the red appliances. Adding yet another on top may be a mistake. Maybe you could go for a red glass splashback and upstands? Or, red metro tiles with grey grout? Dark Grey metro tiles would look very classy. I personally think that the same rule applies as for decorating walls etc. Plain is best and use accessories to add colour. When you get bored with the colour combo you can very easily change accessories for a whole new look. Remember you'll be looking at the kitchen for possibly 10 years, will you always love grey and red? If you stick to the pale grey / dark grey and ivory pallette, then you can change the kettle, toaster, cannisters as many times as you like from red, to turquoise, back to ivory, green etc, but once you put tiles on the wall it's a lot more expensive to change when you've gone off the colour. I only tiled my kitchen around 4 years ago and i'm sick of looking at it already, and i positively hate my black granite worktops.

Behind your range i'd use a stainless steel sheet, Ebay's cheap, but just google stainless steel sheet, available cut to size all over the place. This one for instance is quite a size 2000mmx1000mm Ebay ( Stainless Sheet ). You can then use the car paint and the metal will take the heat as will the paint. Or to go with your colour scheme how about Copper?? copper sheet ( Ebay ) Plain Or, take a blow torch to it for patina??Copper patina sheet glass available from a trader on Houzz [Glass Splashback[(https://www.houzz.co.uk/products/copper-patina-glass-splashback-60x60-cm-prvw-vr~87224336)

Matching granite and up stands, lovely granite. However, many have mentioned that when tying the back splash and up stands together the difference in the two pieces of granite is quite noticeable, so something to bear in mind. I do think however, that regardless of not wanting glass or tile, you do need something behind a hob.

An upstand is the piece onto the wall and also sitting on your worktop. It’s around 4” high. Different people deal with it in different ways when adding something (splashback) to the wall. As Sarah L has said most don’t have the upstand when there is going to be some kind of splashback behind the hob so you may want to cut it out (if possible) and have the splashback direct on the worktop just behind the hob. Some keep both and add the splashback over the upstand which is what you may decide to do now it is already fitted.