I prefer the flexibility of the open design. You can always add another stool, and you can move more freely. Closed is more limiting.

open always looks unfininished rustic is a nice way of saying not finished

Yes, it's the trend and can be very beautiful looking, but so can an island with open sides. My rule of thumb is if people will be regularly sitting at these barstools than I'd consider leaving the sides open so it's easier to get in and out of and less likely for anyone to smack their knee into a side panel. If just for looks more than anything go for the "refined look".

I rarely do islands with sides at the seating since IMO they are best when done waterfall style and in a very contemporsy space . A nice overhang with 3cm material as teel supports are a nice look and no places where soameone feels hemmed in I do not think one is more rustic than the other . If you want real help here we need to see the plan and the style of the space. This is my kitchen not rustic but open seating

I feel like a lot of the inspo pics online with closed panels dont have near enough room for the chairs to be pulled out and used by people -

Option C. Do a real overhang with stretcher bars and legs.

Hi everyone. Thank you so much for the quick and helpful responses. I decided to go with a closed island, but your comments helped me understand the considerations and why that worked better for my particular design and preferences. Very much appreciated.