Celery green

I just finished painting my kitchen! What a job! I went with 2 colors, chocolate and red. I bought a bunch of paint swatches from the store to help me make up my mind. Also if you have a sample of your yellow to take to store with you helps too. I think something in a sage green color might be pretty but I am not a blue person. Enjoy your results!

Sage green goes well with pale yellow easy on the eyes

I'd carry the yellow through, but maybe a softer shade than the bright yellow in the sunroom. In my experience, light blue sometimes tends to show up as gray in corners and angles. :)

You really didn't give enough information. What other rooms can be seen from your kitchen? What color is the countertop? What color are the appliances? What type/color is the floor? Do you eat in your kitchen? IF so, what is your kitchen table like and what do your dishes look like? Are you willing to repaint your sunroom? Do you love the bright yellow sunroom? How much wall space is in your kitchen? If you paid an interior decorator to come to your home to help select a color for your kitchen walls these are all questions that she would ask and the answers would help decided the new color.

I would paint the cabinets white that way you can paint the walls any color and change your mind at any time. If you go with blue cabinets you're stuck with matching the blue color. just mho

I have blue walls, with all my accessories being blue and yellow.

Find a curtain, tablecloth, dishes, anything you like or love..and take a color from that! If it's a strong color, just do a wall or the bottom of all walls ( then get your husband to do a chair rail!! : ) Have fun!

Yellow goes with just about any color. But if your sunroom is bight yellow I would pick a softer color for your kitchen. And maybe do a little accenting in the kitchen with the bright yellow in pictures or nick nacks.
Go to your paint store and pick up some of the color samples you think you might like and tape them up on the wall and look at them at different times of the day. Because light changes in a room threw out the day and your colors will look a little different. Then decide which one you like best. I do this when ever I paint and I have changed my mine on some colors I thought I would like because of the way they look in a room at night time. Paint isn't cheap so if you make several trips to the paint store for paint chips it will be worth your effort. It sound like you like bright happy colors so paint it what ever color you would like you are the only one that has to be happy with it.

I'd either due a pale sky blue (careful its not a 'cold' blue) or a paler yellow, and keep the ceiling, trim and cabinets a soft white. Wouldn't that be lovely with a yellow/blue/white plaid or nice floral for curtains, table cloth, etc., to tie the two rooms together? White can be gray tones, peach/pink or blue if not careful. Benjamin Moore has a "dove white" that is lovely -- used that on all our trim, ceilings & doors throughout the house including the cabinets in my quilt room, and its a really nice soft white. Here in the Pacific Northwest you have to be careful with colors or its too drab all winter when its gray outside.