If the practice of scripted storylines is going to continue (and it likely will), I'd like to see something a bit less juvenile. I've always wanted to see a plot structured kind of like a tragedy -- but with a gaming-style twist. I'm not exactly sure what that could or would mean, but I'm not a developer.

Also, more interaction with the gameworld. Maybe dungeons or towers that have multiple solutions depending on the manner in which its puzzles are solved. For instance, there's a stream preventing your progress: Find a valve to raise a floodgate (potentially flooding or draining other areas in the location, revealing hidden paths or treasure) or freeze the water with an Ice spell (freezing everything, and both missing some good items stuck beneath the ice while creating a make-shift bridge to hard-to-reach nooks)? Beautiful environments are just set pieces. Let's see some creativity with this new hardware

More resource management and less cash acquired for the party. I know that's probably not the kind of game they want to make, but having a modest wallet carefully spent on the right items (or whatever is right for your strategy), and then painstakingly and successfully plundering a dungeon with limited resources can be tremendously satisfying. Finding a hi-potion in a chest should be a cause for a fist-pump, not a shrug.