Haven't done so but please be aware that most upholstered sofa and chair seats may be lower than DR chairs. OR one sinks down in them so they seem that way. Also, when laying down on a sofa behind the table does it block the view of the TV? Measure to be sure.

lucky is right. Most "sofa" type seating is going to be too low for the standard dining table. I spent a fairly long time looking for a settee or loveseat to pair with my casual dining table, which is 42" round. I finally bought the Marcel loveseat from PB: http://www.potterybarn.com/products/marcel-mini-sofa/.

Your Ballard sectional says the seat height is 18". That is around the same seat height as a typical dining chair BUT your dining chair doesn't "sink down" like a sofa does. Know what I mean? The Marcel loveseat works because it has a higher seat height (22") and it's not super plush so the seat doesn't "sink" too much. I'm not suggesting that the Marcel sofa is your solution, but you need a higher seat height than the Ballard piece.

Is a built-in window seat out of the question? That's what I have in my kitchen and I love it. You could make it extra deep with a lot of pillows to make it more comfy.

I wanted to do this in my eat in kitchen. While shopping, I found most standard couches were too low and/or too deep to use with a standard 30" tall table. Even if the seat height is 19", they usually sink lower than dining chairs when you sit on them.

Ballards has dining benches/sectionals. I haven't sat on them but a salesperson said her son had one and it was very comfortable. Lee Industries Coveralls also has a dining bench.

Look for "dining bench" or "settee" in your search.

Lee Industries Coveralls

Ballards

I’d love a dining table that was low enough to work with my sectional. I’ve been looking
at the Kids Carolina Activity table from Pottery Barn, but wondered if there were
adjustable height tables that were
less than
28”?