Hi Just a quick thought on your Booster-pack idea
I think you might be leaving the concept af your game to far behind, being a lot of the gamers I talk to in game seems to be very pissed of about tha fact that you now want to charge money for something we already are paying for ( monthly fee ). a lot started out here because of the fact that you don't charge for the game and that is a nice policy indeed. Well again a lot of people I chat with explains to me that the now are leaving becuase of this change in policy. So well just want you to consider once more if its really worth while to take the risk of losing a lot of accounts. Another thing people are using for an argurment is that Star Wars Galaxies is comming up and others new MMORPG. Well maybe the booster pack idea will save your economy here and now, but just consider if the timming is right.
So instead of changing policy and charging new fee's, and giving the playing community some very strange argumentation about why it costs money (read "Booster packs have been standard in card-based games for years,"), you should rather do everything possible to keep your customer at home...
at last as for your pricing its not lower then the price of a standard Expansion Pack but the same price as an Expansion pack.
Regards From Meja