The NW corner is getting the most hype because the brutality of the conditions there has stood out more than other places, but Western CO as a whole is having a very rough winter. If your main concern is winter kill, there won't be a single quality unit that doesn't see noticeable effects of the winter.
My take, and it might be an unpopular opinion, but there will always be "x" that will make someone question if it's the right year to burn points or not. Rough winter, dry summer, recent fires, etc... Each tag gets harder to draw each year as it is. You never know when your last opportunity to hunt a unit might be.
Try for the tag you want, and hunt the heck out of the tag if you draw it. I am in the same boat with Wyoming this year, I did the math and realized I will never have a realistic chance at drawing the top few units, so I picked a mid-range one that I can (likely) draw with my current points and will start looking into hunts that I can draw there every 4-5 years or so after this year, assuming I draw.
My main point being: if you're worried about the winter kill in the NW corner, just know that the effects of this winter will not be confined to just the NW corner. It will permeate through all of Western CO.