If I know the flight is heavily booked, I will try and snag 1B using Easy Check-In Online 23:59 hours before the departure. I figure if the flight is reasonably full, they won't be doing the re-stacking of seat assignments for aircraft trim.

If the load looks light and I do not have a tight connection, I will book 12C, and enjoy what little extra legroom there is. Flipping the aisle armrest up also helps.