If I recall correctly, that star wars MMO had voice acting in every single cutscene. Unfortunately, because of that, speed of content delivery faltered early on (I don't know the situation now but I remember that patches were slow to come because of the vast number of voice recordings they had to perform for each patch).

For me, the current system of voicing major cut scenes is good. Obviously, a majority of folks have not heard voice acting for quite a while since they completed the last main mission, I think no voice acting for the stuff up to 2.0 is fine.

Why? I would rather have content and bug fixes delivered asap. A majority of the stuff going to 2.0 will up and dissapear (Live invasions, Dalamud etc), so there is not much point to doing voice work for these kinds of things.

Once 2.0 hits, I think we'll receive steady updates to the main scenario quest lines, in which a majority of the important cut scenes will be voiced. Don't forget, they mentioned that voice work will be done for all languages, so that puts an additional strain on how fast content can be pushed out when you are doing Voice work for 3+ languages.

Too much voice work = content gets delayed.
Too little voice work = lose a bit of life of the game.

I think the ideal balance would be just voicing the important cut scenes that relate to the current scenario (or expansion if you will).