its your dining table's fault. standard height is about 30", and yes you sink in some upholstered chairs depending how they are constructed. even though a 'normal' difference is 12" (which would mean a 19" chair for your table), if your bum (and therefore spine) are sinking below the wood frame you are getting less than the measured height. i'd rethink the felt sliders on the table, or else find straight chairs that can be custom made an inch taller. it doesnt matter what the ruler says... you know if you have that sinking feeling..... (we went through this.... fortunately we bought our chairs and table from the same store and werent able to try the sample chairs with our table. turned out the table was higher than all of their other tables. they remade the custom chairs an inch taller and i've been able to eat at the table without feeling like i'm 9.)

The table has a really muscular right-angled solidity to it. It’s wonderful... but I think that means you need some color and curves with the chairs! Judy’s suggestion seems to me like it matches too much with the table and doesn’t jnfuse life. I think the red west elm suggestion is a great one. But I think your paint is slightly on the cool side, so I’d recommend this blue-ish colored chair— https://www.target.com/p/2pc-copley-upholstered-dining-chair-project-62-153/-/A-52962328?preselect=54210220#lnk=sametab

As far as the mason jars on the wall, this is what I had envisioned but I just want everything to be uniform and match is all. Ignore the dark wood... I would prob stain it the same color as the table is stained so it matches... or does it even matter?

Yes I understand the chairs can be bought separately. Is there a specific style you like? Have you seen these at Crate and Barrel. Really pretty and could could update your space I love pottery barn chairs too. They are made solid and sturdy. They worked for us when our children were small.