Bamidbar, when I say Hebrew, perhaps I should qualify it by saying names of Jews we find in Tanach, which IS L”K, even if the name Mordechai has its roots in the name Marduk. Nonetheless in his name there is an element of his Jewish persona, because he was Mo-red against Haman (and I have no idea is this was ever said previously by a meforesh, but I just thought of it myself when I saw the name Mordechai posted). All the names you mentioned have Hebrew meanings. The letters of Esther, though a Persian name, means I will hide, and Hashem did hide Himself from the story written in the Megillah, there is no mention of Him at all. ALL names in the Torah are derivations, but once they are in the Torah, they are part of our heritage, though one would not probably find anyone named Esav (I have met a few Nimrods, though) 🙂
The point I hold is that once Am Yisroel was established, those names WERE and ARE the Jewish names. There is no halacha regarding naming a child. I just feel (clearly very strongly), that names like Shprintzeh and Hirsch are not really Jewish names though they are treated as such, any more than are names like Raoul or Oscar or Miep, all of whom deserve to be honored by Jews for their actions. Look how many people name boys Alexander. These are my convictions, but only I have to live with them (and my kids, of course).