I'll probably get hammered for this, but ...
variations don't matter.
The reason there are variations is because the principle is applied in different manners. Apply the principle and forget about the variations, they'll follow naturally.
kuzushi ... tsukuri ... kake. You can't get kake without going through the others.
Kotegaeshi can be applied a multitude of ways. Learn the principle underlying the technique and don't focus on the technique so much.
Learn two ways ... either focus on internal center and uke will be effected from this. Or learn to affect uke by affecting his/her center. If you learn those, the handwork and footwork is a piece of cake. Or in other terms, the principle is the ura and the handwork/footwork is the omote.
All IMO anyway,