Of all the IPs to be licensed, Dungeons & Dragons is actually the one where real money transactions (RMT, or microtransactions) make the most sense. Why? Because D&D has been doing microtransactions for decades. In fact, of all the games on the market, Wizard101 is the game that currently mirrors the pen & paper D&D model the closest.
Think about it… to start playing D&D, you need to buy a couple of rule books, namely the Dungeon Master’s Guide and Player’s Handbook. With those two books and some dice, in theory, you never need to buy anything else to play. You can make all your characters, make your own dungeons and monsters, you can even make your own loot. Of course, not everyone is as skilled or as imaginative as everyone else, so D&D sells gaming modules which include a dungeon, monsters, loot, and perhaps even a city or town, story lines and quests and events. You need to buy each module to play each module (or at least someone in your gaming group needs to). This is pretty close to how Wizard101 functions, only the DMG and PH are free. Create an account, download and log in. You can play the first few areas of their world for free, and then you have to pay a small fee for additional areas. Of course, there are other things you can buy in the game, items and houses and whatnot, but if you just want to play the game, I believe currently you can get everything for around $80. For many MMOs you’ll pay $50 just for the game box and the first month, and at $15 a month, just three months in and you’ll have spent $80, and you can’t really finish all of most MMOs’ content in 90 days, so you’ll pay more.
Money amounts aside, however, DDO should have been built this way to start. The base game with a small number of dungeons, the base classes and whatnot should have been a fixed price, or even free. Then, much like games release expansions on Xbox Live, put out new dungeons, new modules, for a small fee every month or two. New classes could even be released for a small fee, much like how D&D puts out expanded books to introduce new classes. Perhaps they could have even run a hybrid model, charging players $1.99 or $2.99 a month for access to the game, and then $5-$20 per module (amount based on size of content).
Anyway, that’s just my thoughts. If they’d started with that design, perhaps they wouldn’t have had to switch to their new Free-to-Play/Pay-to-Advance model.