Is it necessary for one who desires sincere repentance to repent only for abandoning obligatory duties, or also for abandoning Sunnah acts and recommended deeds, and for excessively engaging in permissible matters?

Repentance is obligatory for neglecting duties and committing forbidden acts. However, abandoning Sunnah (definition) (prophetic traditions) and Mustahabbat (recommended acts) does not necessitate repentance. Excessive engagement in permissible acts is not a sin unless it involves blameworthy extravagance. The Prophet, peace and blessings be upon him, approved of confining oneself to the obligatory acts. Nevertheless, it is not befitting for a Muslim to continuously abandon the Sunnah and supererogatory acts, as they compensate for any shortcomings that might occur in the obligatory acts.