Organic is a conventional pressure plate (with organic contact material rather than ceramic).
Paddle is a limited contact area plate (typically with three to six paddles from a central section; hence the name).
I don't claim to understand the physics of it because it seems counter-intuitive, but you can hold more torque (and by extension, power) on the paddle clutch. - They're a lot more on-or-off than a conventional friction plate, so not as traffic friendly.
Ultimately they're both limited by the cover plate you use because that's what's proving the clamping force.