Hello spursman.
I steer clear of ECO completely as it makes the car a bit torpid on throttle response and steering + firms up the damping to a more sporty feel.
Other bits like aircon,lighting etc may be worth doing in ECO.
As you have the DCC you can toggle to get the best results from available parameters in Individual and find what suits.
I'm on 12.5k now and have recently done family visits, 200 mile round trip in Normal mode.Got 39mpg going about 50mph for about 30 miles and 90-95 the rest.Used aircon all the way + heated seats for some of the time.
I'm sure the figures will come as it has been cold and your drives seem to have been limited.
Keep on enjoying it.