Is it obligatory for a traveler working far from his family to return to them if he secures a moderate income, knowing that his stay [there] would be without work, depending on this income, and would that be considered ingratitude for the provision?

The family head's mission encompasses material and moral rights. If the father is able to fulfill these rights while continuing his work, then he is not obligated to return and quit his job. However, if his continued work abroad results in harm to the family, or neglect of their rights, or exceeds the maximum period of his absence without his wife's permission, then he must return to them and fulfill his mission. This is because the primary purpose of seeking sustenance is sufficiency. Indeed, he has succeeded who embraced Islam, was provided with sufficiency, and whom Allah made content with what He gave him.