I advice the same MMOs required maintenance and have higher operating costs for what I understood IG intends to only tax per DLC or content package. This means if you need revenue to cover expenses you will have to release DLCs which also cost to produce.
If many DLCs/packages are produced the playerbase who does not have them might feel alienated and populations might go down and the population renewal requiring new players to try & enjoy the game will find a dead server or zones because most the players are not playing on the original game. So if DLC are made to discriminate player populations it will never work and might eventually kill the game.
Also anyone that knows the current MMO market knows it's way too overcrowded , usually players don't actively play more than 1 MMO and 2 is already rare including F2P games..
Plus developing a MMO takes years and requires skillful and experience workers that cost a great deal plus I have never experience a polished MMO that was free of bugs or issues sometimes a bad launch is enough to kill a game like it happen to Final Fantasy, Tabula Rasa and Earth & Beyond.
For a small company like digital reality making a MMO from scratch at this current stage of MMO market maturity it seems like going "All in!" especially when there is a huge potential on the RTS market especially space where digital reality has still a name and label PS: As anyone tried the StarDrive Beta on steam? It's already the 2013 Best RTS by far for me and it still needs polishing tought it's like a serious Galactic Civilizations + Sins of a Solar Empire + Space Empire IV and a little of IG 2 like Spying and overmap.
2013 & 2014 seems to be the year of Space and Space Strategy games with StarDrive, Swords & Stars II (promo), Star Citizen, ELITE, FTL, Strike Suit Zero, Star Commander, Starlight Inception and the fuzz of Nexus 2.
It would be smart to Launch IG 3 as an RTS singleplayer + multiplayer( or MMO after launching the singeplayer) to capture some of the buzz and players StarDrive will revive!..