lighting placement question

Last kitchen I did, my own, I installed the cans 6 inches into the counter top for my peninsula. That area was cooking and prep. I chose the measurement by the diameter of the light at counter height. I did not want shadows. The lights that were by the counter with upper cabinets I installed even with the counter top. I used wall washers and down lights Your light fixture manufacture should have information on this

Even with non directional cans you can depending on make bend the socket braket if angling is off. Halogen lights, the small 55 watt or so are normaly sold in Spot and Narrow flood. But you can order 5 or so different width patterns from Narrow spot to wide flood. I suggest holding up a lamp at the ceiling , wired, and try different bulbs so see what you like . I use three different beam widths depending on the effect I want.