Go ahead and use Bronze. The cable or rod is not very big. The bottom of the light fixture should be 30"-34" above the counter for good illumination.

The cord should match the finish of the fixture. It will look fine. Be sure the canopy of your new fixture is for a sloped ceiling.

You will definitely need to use cord hung pendants as they will be hanging at different levels. Rod hung fixtures aren't threaded all the way through so you can't just cut them. With taller ceilings, I like to see them so that the bottom of the pendant hangs at about the 6' or 6-1/2' area. I would also want them to be able to hold a regular base bulb, aka medium base, aka E26 base. That way, no matter how high up you end up hanging them, you should have enough light for your countertop. (no higher than 6-1/2' of course) :)

Side note: As in Cathy's comment, her picture shows chain hung. You can also do chain hung pendants. Cord & chain hung pendants will all "right themselves" also. I would also choose a larger pendant like in Cathy's comment, because there's a lot of space to fill there.

Click on this link. Something like this would be a nice choice: http://illuminationslightingonline.com/brand-z-lite/1-light-mini-pendant/sku-V1349-189mp-brz