The problem right now is that every time somebody wants a buff to the barge everybody screams "Y U POWERTRADE METAGAMING NUB!"
It isn't about powertrading. It's about the fun of using a barge. The way they are right now, they are basically unusable as they are impossible to protect and are less effective at hauling than a regular transport. They are SRP ships, pretty darn rare, so they ought to be good enough that it's worth flying with escorts and having a large-scale and fun operation.
They need to be given 12x regular cruiser turrets. People keep saying "barges aren't supposed to be a solo ship". They won't be. They are bigger than the biggest battleship, even with 12x regular cruiser turrets they will get killed by pretty much anything. The problem right now is that bombers can hug the barge and just SNAC from 0m while escorts struggle to hit the bomber, with any missed shots hitting the barge. If the barge had 12 regular cruiser slots (which would be filled with cruiser solaris), at its enormous size it would still be unable to kill the bombers on its own, but it would be able to force them to evade and shoot from further away, giving escorts an actual chance at protecting the barge. And "Why cruiser turrets? Why not gunboats or just increased amount of transport turrets?" The barge is incredibly long, and its rear guns can't even shoot past its nose. It needs cruiser turrets just so that it has enough range to actually reach people who aren't laying on top of it.
It also needs a better shield slot. It's infinitely bigger than a freakin' battleship, any shot is an automatic hit. It should be given a gunboat shield. Have a gunboat stand still, and you will see that a VHF can easily drain its shields alone. Considering how enormous the barge is, every shot is an automatic hit, so you can rest assured that even with a gunboat shield the barge would still be quite vulnerable, but the bigger shield would still be helpful.
Barges also need their speed increased. Right now, they are so slow that a Stork can haul more in an hour than a barge, so why would anybody even bother flying a barge and bringing along a bunch of escorts and going through all that trouble? No, I'm not asking to turn barge into a powertrading tool. But it needs to move quickly enough to at least be worth going through the effort of using. Its regular speed should be increased to 40 m/s and its cruise speed should be increased to 180 m/s. It would still be very slow, and considering its inability to use lanes, jump, dock on planets, or turn around in less than three hours, it would not be a "powertrading" tool. But it would be good enough that people could enjoy group operations with barges.
Of course, with all of these buffs, it would need to be made incapable of docking, forcing people to work in groups with another transport (or multiple transports) for unloading and loading the barge. This would make things quite interesting, increase the use of the barge as a roleplay ship while also decreasing its use for powertrading.
If you still think this sounds "OP", come on, you're administrators and developers. It wouldn't take long to make those changes and test it in combat yourselves to see that the barge, even with these buffs, would still be very easy for enemies to destroy, but at least it would be able to keep bombers further than 0m away, allowing escorts to actually have a purpose.