I´m not using 15 at the office as it is yet to be localized but this is what I noticed while doing some test and preparing templates in 15 INT.
It seams like the .tpl file I created for our office launches with default status "New" (as I saved it) and after making some changes, saving-closing and reopen, the default status stays on "New".
This is good right? But I agree that the "True" default status should be "New".
At first I was happy about this new feature but now I realize this will add some thinking while making "foolproof" templates
As for layers we are using a system with different layers for different renovation status where Layer-Extensions are used to distinguish status.
E.g there are three different layers for a wall, Existing, New and Remove.
This system is standard in Swe and unfortunately produces long layer lists.
But by sorting them by extension, and using Karl´s suggested method, it´s less difficult.