Ok fair point, even though I do think you are overexaggerating your scenario. If the actual game truly lacks content I believe no amount of fluff items will be enough to save it. People will still leave, even those who spend unreasonable amounts of dollars to cartel packs. Fluff items are a needed extra to this game, World of Warcraft is very successful with their own fluff content and it is very popular among the playerbase but for the majority of players it's never their primary aim in this game.
I do think that they won't make the mistake of constantly delaying content to rush fluff items in, that would be just stupid on their part.
As long as they have people willing to spend 100's of dollars on a regular basis... then updating the cartel packs will be their main priority. Now dont get me wrong here. Im not saying there will never be content updates. Im simply saying that it is going to be few and far between and more of the same old that we already get. Right now they have content back logged. Meaning, its practically ready to go now. Once that runs out the 6 week content updates will start to be 2 months then 3 months then 4 months. All the while introducing more and more bugs in the game which helps to further that gap.
On the other side of it. Cartel content is probably generating them more money then they have seen from subscriptions. That will die down as stuff becomes less and less rare and people got what they pretty much want. Walllah! New cartel pack content. You have to understand that EA is a business, a greedy cuthroat one at that. They do not care about people. They do not care about the critisim. What they do care about is the sales they are making in the cash shop... thats the only thing they care about. As long as those sales are still being made then subscriptions are meaningless to them. Subscriptions are chump change compared to the money they made in the last few days.
I hope Im wrong on this of course but this is the gut feeling I get. The first sign that Im wrong is if EA hires a bunch more people. If they dont hire a sigficant staff from all this added income then you know that either they still arent making much money OR they dont care about adding more content.