Slightly off topic: the IndoIranians came to India after they left Persia, and the vedic language is pretty close to Avestan. The beliefs of the Parsis and Hindus have been interpreted as a sign of an old conflict.
Thus, at root, Daev is the same as Indian Deva, cognate with Ju- and Zeus, originally meaning the `bright' daytime sky as opposed to the darkness of night, and a generic term for gods. druh, the Sanskrit form of Avestan druj and cognate with Germanic triogan and trügen, however, still means to injure. Conversely, asura (either from a root meaning to be, or, more probably, from one meaning to throw or shoot) whose root meaning seems to be `divinely powerful', are the good guys in Avestan, but, except for rare references in the Rgveda, the bad guys in Hinduism.
So, the association with evil is, as always, ephemeral, but, alas, Hinduism doesn't change the sex of the beings nor does Sanskrit change the gender of the word.