Something like this was proposed a while back.
Such as showing some of the accolade badges you have earned on your ship like how U.S. Navy ships will show awards the ship has recieved.
A Dev had said it would require considerable reworking of of the ship skins and ship tailor to accomplish this.
I would imagine it would be the same your propsed PvP fleet emblem "trophies".
It's a simple matter of how many could be should on one type of ship, couldn't be visable much smaller ship. Like how you Fleet emblem is "big" on a galaxie but tiny on a Defiant.
A Defiant loaded up with 10 fleet emblem "trophies" on her hull would look a lot like modern race cars covered in sponsor stickers.
It, IMHO, would just look bad.