I noticed that the Python reaches a shorter distance than the Transporter 7, even though it has a better thrust engine. Although i had to take in consideration that the Python has bigger weapons, but i believe the engine should support it. Plus they both weigh the same. So here's my take, shouldn't the optimal mass implement how fast the ship can go before dropping. Like lets say if the ships optimal mass is 850t, and your at 660t, shouldn't you be able to travel about 22ly with a max out fsd on that ship, and once your beyond your optimal mass it decreases.