Contemporary homes don't do any type of medallions on the ceiling.

I don't think drawing more attention to your adjustment is the way to proceed. There are various can light covers that can be painted with the same paint as your ceiling. Then cut the hole size you require and hang the new pendants.

Or change the size of the pendant canopy to a larger size. Those are also available.

https://www.architecturaldepot.com/ceiling-medallions-17.html?gclid=Cj0KCQiArt6PBhCoARIsAMF5wajOCHEDXUFL3b2JsPAxxRAQDLajDjgMHYTUPRH9wA5PJdGVF1k91zgaAuyJEALw_wcB

Thank you but we are doing this in a contemporary home. We don't have high ceilings, so the round more traditional style seems more visible to me. They also look inexpensive (which they are, but I'd like them to look better). A simple square would be more pleasing.

Two are installed over the breakfast bar, so I can't go large.