People are more than names and dates. What they did, how they suffered, why they moved, their occupations and passions make the puzzle immeasurably more valuable. Some are officially changed but most change by accident. Not only are their spelling errors but people differ on how to spell the same name. I suggest you keep nicknames as well as official birth names.
Names change due to ease of pronunciation, especially when changing language and country.
For example, Hough is changed to Huff. An s is easily added or dropped i.e. Wood and Woods. Not that long ago people didn t even have last names. The junior may or may not have been official. The assignment of last names varies by ethnic origin and geographical area.