I don't see why a woman couldn't be called "a time lord". It is common and correct to refer to a group of nobles as "my lords" even if some of the group are female, and besides, there is no reason once you set aside human patriarchal norms that a woman couldn't have the title "lord".
I think this series has deliberately steered away from detailed backstory of any description (time war, Gallifrey, River Song, reappearing allies and villains etc) to be more accessible to new viewers. I guess we'll see if the term comes up in the NY special.
I think you might be right. It's a sticky wicket in this day and age of gender equality and political correctness. Now, it is proper to consider any one (male or female or trangender) who acts in a play/TV show/movie to be an "actor" and not distinguish between actors and actresses. But then again, since "actor" is most associated with a male performer, why do we now lump every gender into that category?
When it comes to titles such as Lord and Lady, they have historically been equivalent in all respects:
Definitions:
Lord literally means, "a Ruler, a Sovereign or a Master. One possessing supreme power, a Feudal Superior and the holder of a Manor."
Lady is the female equivalent. It can be used by an unmarried woman in her own right, or by the wife of a man with the title: Lord, Baron or Sir.
The same can be said of other titles... Duke/Duchess, Sir/Dame...
So by definition of the vernacular of our times, Jodie's Doctor would be considered a Timelord, rather than a Timelady...