When ships released, if you logged into the game shortly after the content release and were high enough level you were assigned a ship shard at that time. Since many of the highly active players at the time were anxious to see the new content, we were all assigned the same shards.
Consequently, these shards formed the day that ships were released contain disproportionate amounts of highly active accounts. No amount of whaling or strategy will keep you at the top of these old ship shards.
In my shard, everyone on the top 50 has 7* negotiator or 7* malevolence. All the negotiators have r7 gk, R7 ani, R7 5s or ahsoka and relic ht to start. They all run the same reinforcements with a variant of the 5th, which rarely shows up.
I climb to my #1 or #2 payout every day, and every day that takes me between 5-9 battles depending on whether I was lucky overnight or not.
These daily grinds on the old active accounts are what is causing people to quit and CG should address it sooner rather than later or their favorite, not at all.