Making the Grid Label's change size on different zoom levels will potentially slow down how responsive the map is when you zoom in/out, but we will look into it.

We are planning on allowing the user to control the opacity of the faction colors.

Yes we are planning on doing this.  In fact we are going to create a global view type of page for each server, where you can see all the active territories for each continent, along with statistic like "What % of the territories each faction controls" and "How many of each type of resource each faction is currently getting on each continent"

This is currently not possible with the PlanetSide 2 API.  But if they add it to the API we will definitely implement it.

Can you elaborate on what you mean?