Bear in mind, the stock leaders on the B-Series are actually shorter than what most experienced pilots use... As you learn more, you’ll figure out how to use long leaders and still get the kite moving with a little kick or “whump” to activate and maintain the forward drive.
There are examples of this in both the Launch & Control and Sail Loading tutorials.
Key is, it’s harder to start forward flight when the kite is resting (flat and no frame flex), but once you can flex and hold the frame in a different shape the drive ratio changes to your advantage.