Proposal for tidying up Settings App

the difference between "make connectable" and the activation in ON of the bluetooth?

I'm not sure. I never use it.

fixing the "back" selection, whether it is always the first or the last.)

So the proposal is for always First. This is because pressing back from a submenu - selects the first entry in the parent menu on return. In this way you can move back up through the sub-menu's and exit just by pressing button 1, instead of sometimes having to navigate to the bottom option.