If your flying west then I'd say K as the sun will be on the other side should you wish to look out. I'd choose something in the front cabin, no bassinets there so say like 3 or 4K, so nearer the front but away from the galley. As I understand it the service starts in each corner so you'll be served at the start and more likely to have your choice, or choices, available.

Look at the Wiki and note that seats 7 and 14 have only 1 window as a blank is there.

It's worth keeping an eye on your flight as configurations sometimes happen.

Pete