I won't worry about reflections. Rather, I'd try to ensure that I can get enough lighting in the room.

Wall washers may not provide sufficient task lighting since they are usually used for decorative purposes.

Copied from another thread
The rule I used was to achieve ~ 35 lumens per sq ft.
Take the light output from the individual components that will make up the main lighting. eg - 1 recessed can. Assume ~ 600 lumens per can
Calculate the total sq footage of the kitchen * 35 and divide that by the output per can.

Adjust as necessary - lower lumens per sq ft?
Higher luminous output for individual cans?

Note that the formula I used grossly simplifies things.
For instance
1. It assumes that the light sources are not directed spotlights.
2. The distance from the light source is not taken into consideration.
3. The spread of the light beam is not considered as the actual placement of each light source is subject to other considerations.

Thanks, David -- using that formula, and counting only the cans, I would say that I need 2 more cans. But including the under-cabinet lighting (and an unmentioned wall washer and a couple of small pendant lights), I'm feeling more comfortable.

To lessen the glare impact on the granite, used frosted face bulbs in the downlights over the counter tops. The LED undercabinet lighting should also have a frosted cover. The Ubatuba granite will act just like a mirror and be very distracting. Minimize this with the frosted bulbs & covers. The 50par20's are available in frosted. There are also LED undercabinet fixtures with frosted covers designed for this application.

Thanks, Ginger - I'll look into that.

I have a fairly reflective backsplash and Black Galaxy granite counter top.