With regards to mobile and formatting: We've been struggling with rankings and usage for awhile. Google/Bing/etc continues to de-rank sites for not having a compliant mobile version. That was us, and we had to move. The site renders differently on mobile devices (or smaller devices), and we don't necessarily need all this whitespace, but we are also cognizant of the width issues with formatting content. I think we might be a bit narrow now, and I hope to do some styling experimentation once we settle some bugs down.
Just for perspective, while some of you don't like this format, for over a decade I've gotten constant complaints about how old, poorly done, hard to read, cramped, etc., that the old format was. I've pushed back and avoided moving on, but realize in changing underlying platforms that some of the old styling needed to go.
We are more flexible now, and I suspect we can start to allow some individual custom styles in the future. Making changes on this platform is much easier, and more importantly, we have skills in house. We didn't have that before.
Suggestions for styling are welcome, just note they may take awhile. I'll also say that anytime a large site changes, there are lots of complaints that die away as people develop new habits and muscle memory. I hated the Books Online change a couple years ago, and still find issues, but I'm much more used to it now. Not to say that your complaints aren't valid, but they're partially based on wanting a familiar feel and partially on things that are difficult for you to work with. I am continuing to push for change and filing issues that we have to triage, debate, evaluate, and fix.