Do you like those tables made out of formica or whatever type of molded plastic they use? There are both round and rectangular versions. Also tables with formica tops and metal bottoms. My aunt had a black and white kitchen with red accents, very modern, and she had both types of tables, one small end table made out of molded plastic, and then a formica/metal one for the eating area with rattan and metal chairs. Not the low end stuff, it was high end. Google "molded plastic dining room tables" and you will find some good "image" examples. The formica versions are mostly not-loved antiques, although my friend picked up a high end faux wood table and black vinyl upholstered chairs dining set on the curb in a formerly stylish Pittsburgh neighborhood. They've had it now for almost 20 years in a variety of homes, has held up well in style and material. It's kinda danish modern style.

Looking for chairs to go with this table and chest - table has gold metal base. Looking for chairs to dress it down just a little. Comfy, too. For a beach house residence. Elegant but beachy if that is at all possible. The chairs below aren’t comfortable and come only in a cream fabric. Looking for some color. Thanks!

Not a designer. Based on examples here on Houzz, it looks like she can use any chair. Even her current chairs.

Your color choices are almost endless and really depends on how you want it to feel. Your best bet may be to look at combinations on Pinterest. Just search dining rooms with greyish floors; here are a few different looks.