Hi there, I recently did my kitchen as well, it was a total gut job because it wasn't nearly as good condition as yours. I would say to spend the least amount of money and get the most impact.

You can:
1.) Paint your doors white, get handle-ware. You can even paint your cabinets a dark brown - almost sheen black and get white quartz counter tops so that you don't have to change your sink (they can be bloody expensive and you've got a great sink) Change the faucet as well.
2.) Get stainless steel appliances
3.) Change the counter-top, I always loved the look of the island counter top and cabinets being a different colour then everything else.
4.) A great back splash. You don't have much area for the back splash so get something that really pops. If you're into modern - get something like a stainless steel or mosaic with pearl and shimmer.
5.) Paint! Goes a long way, remove the wallpaper (properly so you don't have chips on your drywall)
6.) If you don't have a dishwasher you should get one, its amazing for resale and you have the space next to your sink - very easy plumbing job, I installed one in my condo and there was non before, cost me $240 of labor plus the dishwasher.

Those are great suggestions. Thanks! Your pictures are fantastic!