Naturally being able to choose keyboards on the fly would be a much better solution. I actually didn't even know this language-based keyboard switching existed until this morning! For your personal use you could just overwrite the default.
For your comment about swiping left/right in system statistics I opened
#2863.
I wouldn't know about battery stats. You could open an issue about that.
The rest is probably tracked in some way or other already, other than switching keyboard layouts.
Regarding closing the book there's actually also "open last document" right underneath history.