I realize my following comment somewhat deviates from the original topic but as it was brought up... here goes.
Regarding seeing large warships out and about from experienced players, there must be adequate incentive to risk 15,000,000gc and upwards ships.
An NPC treasure Fleet composed of high quality warships filled with gold bars might entice me to light up a high priced warfleet.
The risk vs profit eg: my greed meter must win over my caution meter. How much Gold should they carry ?
For me, it will have to be 6 figures or more. Others would have a different personal amount and it could be tied to the difficulty to defeat the NPC Treasure fleet. Danger must be gained when hitting these special treasure fleets so it is not a free gold grab.
As mentioned though, I want to see a 6 figure take when I light up my 8 figure fleets. A 50 k plunder is not going to do it for me. Not sure about others.