Yes if I have time then fighting in Silver to burn down my dark energy capture rate is better. My win ratio there is like 3 or 4 so I am more likely to win about 75-80% of my fights. But if I go to gold rank, I end up losing quite a bit more so the extra 2 chests doesn't seem worth the DEC lost through fighting rank battles. I just find it easier as my cards are not yet leveled enough to take advantage of Gold's increased level caps.