Rewiring a kneelever machine isn't that much different from one with a foot pedal, but you need to follow the wiring diagram carefully as with any setup. If the kneelever turns up, I would go for a rewiring. I easily became used to the kneelever setup, both on my old 99 and an Elna Supermatic. I have never been able to get completely comfortable with hand cranks, with just a few seams or stitches I don't mind, neither with the buttonholer, but for larger projects prefer both hands free to maneuver the fabric, electrical motor and light.
If you already have a hand crank 128/127, the trick with the long bobbins is to wind a few at a time if you know you need a lot of thread to begin with. These models are not difficult to get used to.