Progress
I have finished all of the assignment chains (including all of the officers for critical colonal chain completion) and am sitting at rank 3 or 4 in most commendations (except exploration, which recently saw several mission rewards doubled because it is harder than any of the others and not especially rewarding). I've got 33 very rare duty officers and counting. I'm already at the stage where I only very rarely have to send a green quality officer out on an assignment, and I am steadily converting these officers into blue quality. Even my alt is now hitting rank 3 and collecting blue officers.
Technically, I suppose I haven't won until I max out all the commendations (which actually go to 150K/100K, presumably as a headstart against a future rank 5) and get to run with basically an all-purple crew, but I'm rapidly getting to close enough.
Teaming Up
On paper, there's no reason why you ever need to interact with another player to beat the duty officer system. You can buy and sell items that are used in missions, or even officers, on the exchange, but you can also get most of what you need solo given enough time. However, it has been fascinating to see how the system is slowly accumulating a community following - and how the developers are supporting it.
All of the sector blocks in the game get new missions every four hours. The best missions - depending on your current goals and crew, might be anywhere on the map, and I used to spend 45-60 minutes flying around to see what I could pick up. Apparently, I could have been leaning on a pair of custom channels - DOFFJOBS and DOFFCALLS - along with the crowdsourced tracking sheet. At all hours of day or night, players are manually distributing this information - albeit imperfectly since you can only see missions that you quality for (due to prerequisites and cooldowns).
The new system of NPC's on your ship who offer missions has even added a social aspect. Now it is possible for a player who has an especially rare/desirable mission on one of their bridge NPC's to invite other players to their ship. The very last chain I completed was the 10-part Jem'Hadar mission, in which I was stuck on the very rare 9th part for a number of weeks. The day after I joined DOFFJOBS, someone broadcast that they had this assignment available on their ship and I was able to finally clear it out.
The Business
With my one month of subscription time safely lapsed, I can confirm that I do retain all of the bridge officer and bank/inventory slots I unlocked while leveling as a subscriber. I did NOT, however, retain the currency cap unlock - my balance remained where it was (above the 10-million energy credit cap for non-subscribers) but I was not allowed to earn any more credits. Due to the lack of any indication that this was occurring, I lost probably the better part of 2 million credits before discovering that I needed to purchase this unlock.
That aside, there is very little else that I see myself buying with Cryptic points. I'm happy with my current duty roster limits, and I have no interest in participating in the "lock box" gambling that seems to be getting the lion's share of the developers' attention - this system is now even getting exclusive duty officers and assignments, but it doesn't really bother me that there are officers out there that I will never obtain.
I'm certainly not complaining about the value I got out of the money I've spent on this game - $11.40 for an old retail box along with the points I used to unlock the currency cap and the +100 duty roster for my main. It will be interesting, though, to see where the game goes from here. During the three months I've been playing, the price of cryptic points has gone from just above 200 dilithium to around 300 dilithium - suggesting that the number of players earning in-game currency but not interested in paying real money into the system is growing rapidly in the post-free-to-play era. If the only places where Cryptic is actually seeing return on their time investment is $50 ship packs and gambling boxes, this game could become a place players don't want to do business with in a hurry.