I chopped my daikon radish wide, but still on the bias, and julienned my carrots, but that was just for a nice photo. You can actually just prepare this with a more simple chopping technique.
Additionally, after roasting, you may find a lot of liquid in your baking sheet. You can handle this two ways: 1) Be sure to use a pan with a deep lip and scoop into a serving dish using a slotted spoon, so that excess liquid drains out. or 2) Roast the chicken and veggies on separate baking sheets. I like option 1, because it's less dirty dishes!