At the beginning of the season it's the best moment to actually earn DEC from battles. I always try to make sure at the end of the season that my capture rate stays quite high. Like that I can profit from the big reward pool in the early days. I agree that there are stronger oponents at that time but I believe it's worth it :-)
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Thanks for the reply and insights, @achim03 . I thought so as well, that it is more likely to be worth it!
I try to keep my ECR also high usually, but usually am not so good at not playing.