With IK, you have tools that let you plant a foot where it needs to be so you’re not always moving the skeleton or model to compensate and keep the heel in place.
For legs, IK is nothing short of a blessing. There is no clearly preferable workflow to suggest when dealing with rigging arms and hands, however. Many people use IK on hands as well, but it can be better to animate the legs with IK and animate every other part of the body with FK. IK is best used when parts of the body (such as the feet) need to be planted at times. Planting the hands isn’t necessary for a walk cycle, and having IK handles on the arms may create additional work while animating them.
Rigging the IK Legs
Back to the block man. Switch to that project, ...