Without the battery, the balance will be all wrong!
I don't know the 'blade', as I don't have one, but ALL heli's should balance at the rotor shaft. Turn the main blades so they are fore and aft. That puts the flybar paddles to left and right. Hang it from a loop of thread around the shaft, and the body should be level.
Lack of height while hovering can be many things, first off, charge the battery!
Second, have you damaged a battery cell, so you don't have enough volts? (The radio will still work, but there will be less power).
Third, have you damaged the blades by crashing into something? Chipped or cracked blades create more drag, which need more power to overcome.
Have you damaged the shafts, either the inner or outer, so that one is rubbing on the other?
Have the motors been overheated? This will weaken the permanent magnets, which causes a loss of power, as well!