If they're neutral, though, that'll just make them really popular for griefing which is problematic for a game with no kick function. And this is friendly fire a GUNNER can do, you don't need the captain slot to grief friendly ships, that's a new one. Even if you aren't griefing, it makes it really easy for a quickjoiner to accidentally piss off everyone.
I don't know what to think of these yet. You have to remember that it's a light gun and there's a lot of ships with "useless" light gun slots. The top right slot on a Spire? You bet the Pewter Piper is going to be putting a mine launcher up there. This is a gun that doesn't have to be pointed at the enemy to be useful (though not in the horrible way that personal anti-ship weapons would be) and can be prepped when the engineers are bored. I wouldn't be surprised if they're designed with that in mind, something to add a little extra damage in exchange for whatever utility you would have gotten out of a flamethrower or flaregun or banshee but nothing to actually turn the tide of battle.