I can't recall exactly what the overall 2013-14 and 2014-15 500-mb look was like, but yeah. I somehow seem to remember we really lucked out (particularly in 2013-14) with a more persistent +PNA, we had little or no help on the Atlantic side, and it was a Nina as well. But it worked out!
Another thing, taking these plots at face value for now even though it's waaay out there in time: I've noticed the model cycles that look better, less torchy, or even amazing like last night do not amplify things such that we end up with a ridiculous 588+ dm ridge over the East Coast. Yeah, I know that's obvious, but my point mainly is that while the PNA looks negative, there is a strong ridge over western AK and there's more of a "bowl" like broad trough through Canada and the northern US, with occasional shortwaves pressing down to potentially deliver cold air. That's not something you see in a wall-to-wall torch pattern, and not something that floods Canada with warm air. I'm kind of encouraged by that look! In a way it almost reminds me as well of February 2007, there was a wide, broad trough that covered much of the CONUS, or something like that, which enabled delivery of very cold air from Canada. If one ignores the color shading for the anomalies on the map above, and just look at the overall height contours, you can maybe see what I mean here (there's also a hint of confluence in the northeast).