RNGesus just hates you at the moment...but it really is random. my last set of 9 gave 3 silver, 4 gold and 2 plat, set before that was 8 silver and a plat. It all depends on if the RNG hates what your wearing that day.
Are you saying RNGesus is more likely to bless those who wear sandals?
The spoiler below contains my armies.
Advice is always welcome.
Below that is a link to my army thread with even more details!