Yes that's correct, and could be even more depending on how high the counter is. According to the National Kitchen and Bath Association (and I'm not saying this has to be taken as Gospel, just some helpful guidelines): Minimum clearances for each seated diner are: - 30" high tables/counters: 30" w by 19" d counter/table space with at least 19" of clear knee space. - 36" high counters: 24" w by 15" d counter/table space with at least 15" of clear knee space. - 42" high counters: 24" wide by 12" deep counter space with 12" of clear knee space. If you don't have legs or a solid return / panel at the end of the counter overhang, (e.g., you're using corbels or something similar for support), people on stools could potentially scoot to the side a bit. A leg at the corner looks pretty but limits your space a bit more. Are you using the counter for regular meals, or just casual sitting/snacking/socializing? If you plan to eat meals there, try it out with four people on one side of an 8' table and see how it feels. (Or if you don't have an 8' table, try 3 people at a 6 footer.) You may find that your elbows are knocking. FWIW: We keep 4 stools at a high counter (about 43" high) that's about 84" long and 18" deep. When we have 4 people there, someone usually swings around a bit so they're more at the perpendicular end of the counter run. (No legs on the counter overhang; we have corbels.) That works fine for snacking, socializing, or quick casual meals. 4 people sitting straight on for a meal would be too tight. Here is a link that might be useful: 40 kitchen planning guidelines

I think the ones you chose would look nice. Even though they're modern, everything is square which I think will work really well with all your other elements. Totally different than what you've chosen, here's what I'm getting for mine. My house is early 1900's and I'm doing white shaker cabinets too. I know the kids will love the spinny seats, I just hope that novelty wears off quickly. ;) http://www.wisteria.com/Coopers-Small-Draftsman-Stool/productinfo/W2498/

Redoing the wrapper with something dark walnut or cherry? If you have some inches - wrap with shallow depth bookcases. A good cabinet guy could make you matching wainscot and tint it close to your existing cabinets. For that matter, you could always pull the island completely and replace with a matching or contrasting new one with legs or corbels or lowered surface or whatever else you want.

The Shaker stools I had made for my kitchen may be something that suits yours. They're lightweight and clean-lined but extremely sturdy and comfortable. Mine are maple with walnut stain, but I think they'd be nice in cherry in your kitchen. You could get the taped seat done in shades to match your banquette upholstery. While mine are the classic check, there are other weave options. We have 4 w/ backs @ the island and 2 backless stools for extra seating. I will try to post my first pictures here to show you.