Right, but lets carry that line of thought through to completion. How is "more important" being quantified? The direct answer of course is money. However, the indirect answer is maintaining a game that has something for everyone. I agree that more PREs brings more options to the table, which creates more build possibilities and strengthens current builds, which is why I would still like to see PREs get more attention.
Branching off and creating different quest structures and objectives is another way to keep things interesting. People have to stop harping about it and try it out though, or else they see their own preference being the only thing Turbine could do to keep them happy.
I think you answered your own question of: Here with: You go somewhere else for your RTS. As a business someone must have determined that it makes sense to reach into that realm for Turbine in order to add another dynamic to DDO in order to keep their user base interested.