What is the Quranic instruction to Muslims in dealing with a murder?

**In the event of a murder we see the following instruction in the Quran...** "O you who have believed, prescribed for you is legal retribution for those murdered – the free for the free, the slave for the slave, and the female for the female. But whoever overlooks from his brother anything, then there should be a suitable follow-up and payment to him with good conduct. This is an alleviation from your Lord and a mercy. But whoever transgresses after that will have a painful punishment." (Surah 2:178) What does the Quran mean when it says, "the free for the free, the slave for the slave, and the female for the female" in the murder context? Does it mean that if a free man kills a slave unjustly then one of his slaves must be put to death for his crime? What if that man doesn't have slaves at all? What if a man kills a woman, does this mean that a female member of his family such as mother, sister, wife, daughter etc., must be put to death for his crime? If a woman kills a man should a male member of her family be put to death? Likewise, if a slave male kills a free male then the owner of the male slave must be killed for the crime? In the murder context, the Quran could have said simply, "The murderer must be killed!" But it doesn't. It is almost impossible to guess why! What could be the possible reason behind this ambiguity in Quran regarding one of the significant issues of human societies? The above verse deals with the murder. It seems it is replacing the previous rule given to Jews as the Hadith literature mentions: https://www.sunnah.com/bukhari/87/20 . Some suggest that the verse had a context, which is not mentioned in the Authentic Hadiths though. But that doesn't restrict its applicability to Muslims now. If muslims today are expected to take its instructions how should they understand and apply it? Furthermore, even if the suggested context is a battle settlement between two tribes, which had once fought with each other and later joined Islam, how can it be equal let alone justice if a freeman be killed now for a free man that was killed in the battle? Or, a slave to be killed now for a slave that had been killed before? Or, a woman be put to death now for a woman that had been killed earlier?