Main layout is fixed at this point, and I'm not too concerned about the traffic element. Old layout was worse on that point, and there just isn't a lot of kitchen-dining room traffic other than during the (occasional) dining room meal setup, so folks brushing past the work zone is fine. We don't operate with the traditional clear differentiation of cook zone / onlookers - it's generally much more of an 'all hands on deck' operation [someone at the stove, someone else prepping other aspects of the meal, kids setting tables or otherwise assisting, etc.] and I feel like the cooktop itself is relatively well protected by the island from folks going by, while the prep sink means you won't be dodging people getting to the sink when draining a pot of hot water (a problem we had with our old layout.) I also prefer this orientation as it keeps the individual prepping facing towards the public areas of the house / looking out windows, so it's a more pleasant orientation within the space itself.

Aside from all that we are well underway with construction / busted slab for plumbing / etc., so at this point those elements are a done deal ;)

We may also at some point flip the uses of the 'library' and 'dining room' spaces, though that's still up for debate (I'm team flip them, husband is not.)

I suppose the one element that isn't really fixed is the exact location of the cooktop along that wall, though windows will be ordered this week so need to nail it down. But it is at least feasible to move it to being more centered on the island vs. centered on the wall space.

Honestly a better layout would have been to switch your cleanup sink and your cooktop. That way the cooktop wouldn't be in the work flow area and the cleanup sink would be closer to both the dining room and the breakfast area.

And yes, I understand it's too late for you, but the comment is for those who are still planning their kitchens. There are lots of lurkers.

Are you willing to separate the columns or would you need them together?

The aisle with the cleanup sink is the main pathway - putting the cooktop there would have meant all the traffic going through the work zone. I don't see why that would improve things? The design here was purposeful to keep traffic OUT of the main cooking area (I know there is a door to the left of the range, but it's very much a secondary door that won't be getting heavy use, so that's not a main traffic flow - if traffic is going through the kitchen it will be along that aisle where the clean up sink is.)

And yes - if we get columns I am happy to split them.

I think I would make the island rectangular instead of L shape.