I don't mind dark themes, in fact I am using a dark theme on one of my blogs. However, I do find white text on a dark background is hard to read, often it seems to blend in together and I really have to focus to make it out. Sometimes if it appears interesting I will use my mouse and select the text turning it into a white or blue background to help follow where I am reading, but often if I can't read it I'll look for another site to check out.
Now a way to help that without changing the theme, and keeping it a dark theme is change the text color from white to something easier to see. You could try a grayish text, not to dark and not to light (or it be the same as white). If you like reds or blues, you could use those as well, but not bright colors, more dull works best in my opinion.