Bigger Ships Give Less Treasure!

[stratocaster]

Pretty much all I do in this game is sailing and I've noticed something. I was sailing in my war sloop and I found a spot where a flagship spawns. I disabled and boarded that flagship about 50 times and every run I'd end up with 3-4 royal chests (out of 9 cargo space).
Then I went and bought a war galleon and sunk the same ship like 20 more times, and I'm getting zero or just one royal chest per run (out of 16 cargo space). I went back and sunk the ship a few times in a light galleon and got like 2-3 royals per run (out of 7 cargo).

Did I mention that I have 5 points in treasure sense? The programmers made it so that when you have a big war ship, your chances of getting royal chests is greatly reduced!

I don't know if this applies to the standard galleon or frigate as well. It might.