Hi Ashley,
Thank you. I am personally not real crazy about sloped ceiling cans. Nothing bad about them I just personally don't like the look. If you want a clean flush look however, they are the best way to go. The alternatives are eyeballs and there are several types. As for the layout, 6 or 8 lights total in each room should work well.
Remember two factors about the natural light in a room. One factor is at night there is none, unless it's a bright full moon. The other factor to take into consideration is if a room gets a large amount of light on one side it can appear dark to your eyes on the side opposite the windows. One way to offset this is to have the lights on that side of the room switched seperately. That way you can light the dark side of the room when needed for a visually pleasing effect.
Hope that helps
Paul