The spacing of the pendants sounds pretty good. I'm skeptical that the little 4" models will look proportionate to the island, or cast enough light to work by, but that's probably not critical at this stage; it sounds like your builder just wants to install the rough wiring and ceiling boxes. As for can placement, many builders prefer to put cans out over the aisle spaces. While this does make exact fixture placement more forgiving, it also makes it inevitable that your own body will cast a shadow over the area of counter where you're working. I'm of the 'directly over the counter edge' school of thought. This prevents such shadows, but also places noticable splashes of light across the upper cabinets, which makes it necessary to place these cans especially carefully. With 9' ceilings I'd probably use 5" or 6" cans, shoot for about 4' spacing over the counter edges, and plan to use 75 watt, 40-degree floods.

At 18" apart, your lights are approximately at quarter points, so personally I think that is ideal (from a visual perspective). A friend of mine has a similar size island to yours and has her lights at quarter points. She has 12" pendants and they offer plenty of light for the entire surface. I think the size will depend on the style you select. In my previous kitchen, I had a 60" island with only one pendant centred over the sink. It was perfect for us, as we also had potlights and plenty of sunlight (3 full height windows, w/ patio door).

@Porter, I didn't get the LED Edison bulbs yet-the store where we got the pendants gave me 3 halogen bulbs to see if it was better for me as I didn't like the yellow light at all. I am still going to order them when I do a Prime order to see the difference. That fixture is in a nook--off centered from the pendants--it comes with a chain ;however I am undecided if a table is going to go there or it will stay open, so had it semi-flush mounted. Does it look odd or out of place? @Beth, Right now they are 34" so when the quartz is installed, it should be about 32 33" from counter to bottom of lights. They seem high, but any lower they are going to be in our eyes.

Hello everyone!! I NEED HELP!!! I purchased 2 Duke Oversized Pendants (16 inch overall diameter) in 2020 on Pottery Barn site. They make my whole kitchen!! The glass on one of them broke and Pottery Barn site says No Longer available! Ive been in tears for weeks!!! Can anyone tell me where I can find one of these?? My email is ginamt2@yahoo.com. Thank you for any help you can give! Ive attached a pic of the pendant and one of my kitchen so you can see the beautiful lights above my island!