Hi, since your opponent has only one DC and tends to attack on the flanks, you should protect your flanks and hit him in the middle. I think 4-3-2-1 X-Mas Tree could counter this formation. But be sure that your only MC in the field is at least equal or stronger than his strongest MC. You can choose 4-4-1-1, but I dont think 1 AMC and 1 ST could pierce his defense.