5 gunboat turrets does give it enough firepower to fight, but it won't be able to fight as well as a gunboat, due to both a larger size and lower power (and fewer turrets than most gunboats). I agree that it should be a 'special' ship only used by people who really want it, not just a good ship. Even with 5 GB turrets, it won't be used by PVPers due to the inferiority to gunboats, it won't be used by powertraders due to its lack of cargo, it would only be used by people who wanted it as a unique ship. The Yacht is supposed to be heavily armed, the infocard even says so. A single GB heavy weapon might accomplish this, I don't know.
Kusari Yacht can fire 7 forward transport turrets, which is as much firepower as the Pirate Transport had in 4.84, plus far better maneuverability. I don't know how this translates into the rebalanced 4.85, but the old Pirate Transport was dangerous. With almost freighter maneuverability and 7 forward transport turrets, I think the Kusari Yacht will be pretty dangerous versus fighters and bombers at least, much more dangerous than the generic Yacht is currently. If it wanted to fight, it could.
CDs aren't really a big deal, just that if one has one, then both should in my opinion. Without CDs they couldn't be effectively transformed into pirate yachts. If you don't risk someone using them for pirating, what's wrong with giving them the ability to fight and run away? Inferior to other transports for powertrading, inferior to gunboats for PvPing, filling a unique position as 'blockage runners' who can fight or flee their way through hostility to deliver their passengers/goods safely. Seems pretty balanced to me, and it works thematically.
