I don't like the upcoming change either. I'm a firm believer in the philosophy that "it's not yours until you sell it," as it reconciles the PVE and PVP sides of loot struggles. If you PVE you gotta sell before it gets taken, and if you PVP you gotta take before it gets sold. It's a simple and easy win condition that works in every other aspect of the game, from Reaper Chests to Emissary Flags to Chest of Fortune to Skull of Siren Song. So why is it a problem specifically for the Burning Blade? How can Rare say that selling under pressure is not intended?
Yes, it is hard to stop the Burning Blade if they run. But that crew secured the ship themselves, so the ship's advantages are their privilege. Telling the crew that put in the effort to take it and level it that they're obligated to defend it betrays the above philosophy and it's going to tilt the scales of PVE/PVP engagement. Why would anybody bother with rituals and leveling up with the new system? The added insult is the BB crew gain nothing from defending their ship, which is a longtime complaint about PVP that is normally placated by not having to engage at all.
Let me give a live example from this morning. I took the BB uncontested and started running rituals. Nobody bothered me, the few sloops I seen all gave me a wide berth. Then I got to the 8th ritual site at Barnacle Cay and there was a freshly spawned Galleon at Ancient Spire. After finishing the 8th ritual and setting sail for Reaper's, I see the Galleon had set sail and was in hot pursuit. Mind you I wasn't "running," I hit 8 for the commendation and was going to sell anyways. By the time I reached Reaper's the Galleon had effectively caught up, cannoning over to try to stop me but I was able to sell it with seconds to spare. With the new change I'd be screwed here, putting in 90 minutes of work for 8 rituals just for a fresh faced Galleon to get a lucky spawn and stake a claim in my work. This isn't even factoring in the other ships on the server that could just park at Reaper's with the new change and stake a claim too, they can server hop until they see a juicy stack and straight deny a turn-in.
I certainly feel like there's better alternatives than locking out the ability to sell. Making the Blade easier to stop is the most apparent, "balancing" it better to make sinking it more practical so that running isn't as easy, but I know a lot of people love how powerful it is (including me!). I think another possibility is to spawn more treasure on the BB; the current treasure is so weak besides the COF it's not even worth selling by the BB crew. Putting more valuables on the ship gives the BB crew incentive to park and sell leaving them vulnerable, and/or gives attacking players a consolation prize if the BB crew sells the ship and the treasure gets left behind. Another option is to server merge the BB crew once sold and leave the ship there for a bit so another crew can claim it, which also addresses the common complaint about only being able to claim AI ships.