I don't think Dream Theater is in a rut. The reason that the self-titled sounds like standard DT is because that was their goal with their last album: to make a concise statement of what Dream Theater is about, which is consistent with their decision to self-title it. From John Petrucci interviews:
"Well, it’s sort of like, you know, renewing our commitment to what we do, to what we love to do, to our fans that have been with us for a long time in this thing. The band, this year with this album is just as enthusiastic and passionate about what we do, we’re excited about it, we’ll never stop putting our best foot forward. We’re always going to love doing this kind of thing and we wanted to illustrate that with the title, and share that, demonstrate that the music we have been doing for a long time is something that we believe in and it’s something that we still feel really strong about. And we also appreciate everybody that stayed with us for so long, continuing to like that kind of music. In a lot of ways its a renewal of our commitment to the music and to the band and it felt like the right time to do it, for sure, on this album."
"Because we believe that, although we have a very deep and rich history and we’re incredibly proud of everything we’ve done, we’re still making our best music. So we wanted to make a point of that. The other thing is that a lot of our longtime fans already have their favorite albums of ours, but newer fans don’t have that reference point. We wanted to make this album a reference point for them as far as what Dream Theater is all about. That was the goal and the mission, and it set the tone for the entire project."
From Jordan Rudess:
" When we started to put this material together we felt like you know what? This is an album we can really put our stamp of approval on it and this is something we can really call Dream Theater because we felt like this is so representative of where we are as musicians and as people that if anybody asks ‘what is Dream Theater all about?’ well in 2013 this is our presentation, it’s who we are, it’s totally us."
From James LaBrie:
"I think with going into this album, it was just about us saying, ‘ Ok, look. We don’t have anything to prove. It’s about us being ourselves and writing an album that we feel epitomizes who and what we are as a band’. So what better time in our career than now to write what we felt would support that with a self-titled album."