Is retribution (Qisas) obligatory for head wounds less severe than the Mumidah?

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Retribution (Qisas) is not obligatory for wounds less severe than the Mumidah (Harisah, Bazilah, Badi'ah, Mutalāhimah, and Sumḥāq). The evidence supporting this is that these are injuries that do not reach the bone, thus Qisas is not due, similar to the Ma'mūmah. Furthermore, in these lesser wounds, ensuring that the retaliation does not exceed the original injury is uncertain, which is analogous to fractures of bones. If Qisas were enacted without measuring the depth, it would lead to taking more than what is due. If the depth were measured, it would result in imposing the ruling of a Mumidah on a Badi'ah or Sumḥāq, or the ruling of a Sumḥāq on a Badi'ah, because the flesh of the injured person might be substantial enough that the depth of their Badi'ah equals the depth of another's Mumidah or Sumḥāq. Since the depth of the Mumidah itself is not measured, similarly the depth of lesser wounds should not be measured for Qisas.