Congrats! I have had my new Telluride for over a month now and love it. I tried to avoid all dealer add-ons but it came with carpet mats.
For accessories, I purchased TuxMat floor mats for all three rows. I purchased the Canadian KIA trunk liner to cover the trunk and back of the 3rd row seat as well as a 3rd party back seat over for the 2nd row. Planning to put on Weathertech mud flaps.
I do want to put on a Thule Motion XL Low cargo box with the Thule Edge Tower Cross bars to carry my skis.
I don't think there's an official break in period on the engine, but I have scheduled to have my oil changed this week and I have almost 1500 miles on it. I plan to follow the every 5000 mile oil change to ensure longevity since I tend to keep vehicles longer than most...