Domains vs Domain Aliases... Why?

[ephigenie]

yeah for newer version we're planning to change the domain.tld = username to something else in terms like login with vu2xxxx or something like that.

Within this concept we'll merge a lot of things together so that there's no /var/www/virtual/<domain>.<tld> dir but a /var/www/virtual/vu2xxxx/ dir with extra dirs for domains below that.
And of course only dirs that really need to be there - as a result of it :

-no restriction on deleting a former main - domain while you still want to have a former alias domain
-no restriction on features "only for main domains"
-no must for a directory