Wow. A lot of good thinking and question asking and advice giving. Really the way to work throug it but I think you may be focusing on all the details too much. It's overwhelming. And everything at once, which is why your brain probably feels like it's melting right now
Try for the big picture first.
My VERY simplistic take on it is:
1. Trainingwise it's always better to be able to ADD things.
2. Diet wise it's better to be able to take things away.
Not meant to be a manifesto, of course.