That is saying very little.
Half Life 2 still had a very narrow focus. Yes you could drive 'around' in circles or follow the linear path. Mind you, I am not dissing Half Life 2. It is one of my all time favorites.
What I am trying to say is that games need focus, because they cannot recreate life itself. If they try their limits become even more painfully obvious. Every game has its facades, its curtains you are not supposed to look behind.
I would love it if FD succeeds in combining a first rate shooter with a first rate space sim, but the scope of the Elite universe means that you will necessarily bump into the limits of it.
For example as far as the game world is concerned I would be perfectly happy if you would not be able to enter completely realized cities if they can not be created in a convincing fashion, with a convincing population and interesting stuff to do. Because what otherwise would be the use of such cities and what would be the point of having them. You would immediately be confronted by the limitations in a very disturbing and immersion breaking way.
One of the best open cityworlds ever created is Liberty City in GTA IV (I am still waiting for GTA V on PC

). The detail of that city is staggering and never seizes to amaze me. To this very day I play GTA IV several times a week just to enjoy that wonderful open world. Nevertheless the limitations are clear. The AI, although great fun, has only a very limited amount of options. What you can do in the city is very limited also and the freedom of the game really is just an illusion that breaks down almost immediately when you think about it.
Nevertheless at the moment there is no other game that offers such a large and meticulously detailed beautiful city simulation.
Imagine what would happen in Elite D. if their cities offered even less to do, a more limited AI, a less convincing population, even less interiors etc. It would be incredibly boring and immersion destroying.
I think that it would be much better for the player if he understood from the beginning that there would be no open cities like that in Elite D. You would land your ship at the space port and get access to a limited but reasonable area. The explanation for this would be that on heavily populated worlds pilots are not allowed to fly around at will. They would be directed to certain spaceports only. This is a severe limitation, but it would prevent a player from wandering around lifeless cookie cutter cities that have nothing to offer whatsoever anyway. I feel such limitations would be best for creating a solid immersive experience.
This is just a very specific example, but the same goes for creating fps shooter mechanics. To do this FD would in fact have to create a game within a game. Creating a good shooter is an art in itself. You need to balance weapons, they need to feel right, look good, have interesting mechanics etc. then there are things like player physics, interaction with the environment, cover mechanics etc. etc. etc.
In a massive open environment like elite's FD cannot resort to create some second rate fps mechanics. It has to be excellent, otherwise it would only become a source of irritation every player would loathe and it would drag down the entire game. So adding this will necessarily require considerable resources.
So that is why I feel that FD should choose its battles wisely and not try to recreate life in its entirety in Elite D. They need to make some painful, but smart choices to make this an awesome game. Trying to do it all will more than likely break the game.
In short: Limitations are good.