No doubt the direction of take off will be commented on by AAIB in the final report. For example if the wind benefit is negligible it may be beneficial to land on a runway with an uphill gradient or take off with a downhill gradient.
Another factor to consider is that when using 02 at EGSX you have Stanstead directly ahead (and they may give you a squawk whilst on the ground at EGSX) and when using 20 you have Stapleford ahead.
My understand is that for landing the Hunter at EGSX he preferred 20.
Note. Last time I commented about runway gradients and choice the mods deleted the post.