Well I think choosing an an accent color for your retro kitchen provides an opportunity to give the space a dose of your personality and looks beautiful too.

All neutrals so far - you can add any colors. Depends on the look/feel/style you're going after.

I understand going with the grey since it is an 80's style house. You could also do bright bold colors. I do not know if that is your style. I have attached a quick rendering of the gray scheme you mentioned. I prefer light colors above dark colors. This keeps in theme with the sky and earth. Makes the house seem more grounded. The dark entry also draws your eye to it especially with the light coming from the other side of the house. I have also attached a quick rendering of a blue scheme. It looks like you are on a beach and I thought this would blend in with the surroundings. If that is what you are seeking. Hope this helps.

Is this picture taken during the day or at night? If it’s daytime your kitchen must not get much natural light. Go for white cabinets to reflect as much light as possible to brighten the room up. Boring but timeless & always looks fresh. For colour you could do a splash back, or just add colour via accessories such as a bright kettle/toaster set, tea towels etc., easier & cheaper to change if you get tired of it.