Island counters and breakfast bars demand a combination of task and general lighting. A very good solution is to add a group of miniature pendants.
Mount each pendant so that the bottom of the shade is approximately 66″ above the floor so it is possible to look across the room below the pendants. If the shades are not very deep and there is seating at the kitchen island or peninsula, install the pendants a few inches lower (60″ above the floor).
In general, you should install one pendant for every two feet of counter space and try to use an odd number of pendants to create better balance. Thin, narrow pendants, however, might look more pleasing with the addition of one or two extra fixtures.