Next week, try a different test.
Instead of using a tank that is weak against the missing element, use a tank that is weak against an element that you’re enemies can attack. I went 4-4 last week and only racked up a C Defense for the week and had a nearly fully emblemed defense.
I don’t think that early poor results necessarily lead to great defensive results.
I’ve also had A defense when winning 18 or 22 on offense, so there’s that as well.
It’s largely RNG, but being able to put out 5 heroes with fully leveled Troops is definitely an advantage that those using 3-2 and mono in particular would not be able to match.
Regarding this week, I’ve found that my defense tends to do better with Rush Attack - it’s difficult to overcome a bad board, especially with the right tank in place.