I would prefer that a page looks up the heirarchy for...
one_of_my_ancestors/environment/layout
one_of_my_ancestors/environment/css
I have implemented this scheme in
pieraddons/Pier-Jetsam-Environment
It was much easier to do with the current code, than when I last looked
at it a couple of years back.
I think that there are some advantages to doing it this way, so I hope
you will take a look.
One being that it is possible to put administrators instructions in the
"environment page". So having created a layout, there is a place to put
"design intent" information and to coach your users as to how to use the
design you have made. A notable feature of existing successful CMS is
that they have lots of docs to coach the users and admins through using
the system. Pier is somewhat bare in this regard.
Secondly this establishes a pattern, that "settings" is not the only
place to put setting/parameters. I can write a plugin which can have
heirarchically inherited settings, scoped to my part of the tree,
without having to put a new setting field into every page. The plugin
can look to an environment/settingsforplugin page.
Thirdly, environments can have environments, so that when you are
editing an environment layout and you mess it up, you can continue to
work, because you will not have broken the environments/environment.
(this was possible under the old scheme too and worked well)
btw great work
Keith