feature req: How to specify profile and set of packages?

[VsyachePuz]

There should be possibility to specify the overlay with profile (profile contains the list of default packages for @System set).

It is unclear for me, can profile can contain URL to binary package server or not? Can it contain FEATURES variable? It is important to fast .iso assembling without lengthy compilation.

There should be possibility to specify the URL of /var/lib/portage/world file.
There should be emerge @world command or similar somewhere it the scripts