"I am my own person" can mean "I'm my own boss," but you could also understand it to mean "I am a distinctive person; I have my own special qualities; "I am not a drone in the Borg hive-mind," etc.

Would it sound strange in Russian to say У меня есть свои личные качества ("I have my own personal qualities") or У меня есть свои свойственности ("I have my own characteristics") or У меня есть своя изюминка ("I have my own je ne sais quoi")?

And I also thought that изюминка (literally, "a small raisin," but figuratively, very close to je ne sais quoi) might fit what Valda was looking for.