"leading edge the one when chord% is equal to zero???..."

That's right.

"thrust has to be more than the weight but less than the lift and more than the drag"

Nope, in any steady speed flight condition the thrust matches the total drag and the lift matches the weight. This not only applies to level flight but also to a steady climbing flight. But in the case of the climbing flight power has been added and that power went into creating enough extra lift that the plane is climbing and possibly going slightly faster.

The only time the forces are out of balance is when the plane is accelerating in some direction. This can be speeding up, slowing down, or transitioning from one climb rate to another. Level flight is 0 climb rate, + is accelerating upwards or pitching into a climb and - is accelerating downward or pitching over into a dive.