I would start by making on long cushion across the back on the bench those pillows look like a real PITA with kids and also clutter up the space .All one style of chair would be IMO a good choice since you already have abench and too many different seats are just a mess . I like these and maybe in a color .

Actually, before the chairs, I'd get a new dining light, more linear perhaps much larger art and adjust paint behind

Then...... select a chair from those colors....make a better blend between farm and mid century :)

Minted art ....All modern chair......

And yes, too many pillows, too weak in color

jazz up the pillows/fewer/lumbar

48 x 70....330.00

https://www.minted.com/product/art/MIN-ARC-DNA/colorful-abstract-seascape?art_group=art_print&artist_signature=unsigned&border=full_bleed&frame=walnut&framing=framed&material=standard&quantity=1&size=24x18&utm_medium=sem&utm_source=google&utm_sub=pla&utm_campaign=G_S_Art_Fine_PLA_USA_PerformanceMax&utm_custom_a=FineArt&utm_custom_b=feed&utm_custom_c=shopping&utm_int=b&utm_keyword=&utm_device=a&AudId=&gclid=Cj0KCQiAsoycBhC6ARIsAPPbeLt5rKQCY-ydYX8DB00wFZExoH0N6DQqmH_V_EqKgyyi_8ykMKvYogsaAjPwEALw_wcB&color=A&shape=

It would be nice to rethink the banquette area to better coordinate with living room’s feel and only then decide on chairs.

https://www.target.com/p/wellfleet-woven-leather-metal-base-dining-chair-project-62/-/A-82553869?preselect=82267515#lnk=sametab

A faux leather would be a durable way to go and in a Carmel or brown to add some warmth.

Maybe Incorporate a few sold rich color pillows along that back area of the banquette.

Thanks all! I took your suggestions and I've ordered a new light fixture (Sputnik mobile style) and a modern-style green upholstered chairs. The pillows will get replaced in time, but there's only so much I can do right now!