I don't really care much about specific "directions" they should go into. I neither care much, or even categorize, DT albums that way.
What I wished they did is to stop writing for the clock. JR has alluded to that they've had specific amounts of audio time for a given album, and the moment they clocked the full time, they stopped writing. And of course TA was even more framed by the length consideration.
I feel that, and this is of course pure speculation, that if they stopped looking at the clock, they might be more willing to cull fluff, which IMHO has been a major issue with their latest efforts. They still have excellent musical ideas, but they often get drowned in a sea of stuff that, I feel, 15 years ago would have ended up on the cutting floor. Who knows, maybe that was one of MP's big contributions, to honestly tell JP and JR "nah, I'm not feeling that one. Got something else?".