The idea is, are you basically a good Drow or evil Drow?
Honnestly this is nearly my only problem related to this thread. Should our races and subraces choice influence our "alignement" and how the world react ? According to me : no. A drow is a drow and good actions should lead to good reactions.
I don't really care but I don't understand this choice about drow as a race with subraces. This is even not really subraces...
I dont think choice of your race is influencing your "alignement" at all ... O_o
I mean, in EA you can certainly play lolthsworn Drow who help druids and tieflings, and overall is so good, he almost have halo ...
Also you can certainly play Cleric of Tyr that is so huge a*****e that even Baal would be ashamed of him. O_o
So ...
Feel free to call me foolish, but i believe that subrace of your Drow sugest that in some futher parts of game we will visit Menzoberranzan (or more likely some smaller Drow-focused area) where our red/white eyes will give us some unspecified options in dialogues, since NPC will expect us to be one of them.