I use a similar technique for a very simple plugin system. The main object is a Moose object, and all of the plugins are Moose roles. With in the main class (call it MyApp), I have a method:

sub create_with_roles
{
    my ($class, $roles, %args) = @_;

    for my $role (@$roles)
    {
        next if $role =~ /::/;
        $role = 'MyApp::Role::' . $role;
    }

    Moose::Util::ensure_all_roles( $class, @$roles );
    return $class->new( %args );
}
[download]

... and within the drive program, I can write:

my $app = MyApp->create_with_roles(
    [qw( List Of Role Names )],
    %constructor_arguments
);
[download]

... and get back an object which is an instance of MyApp which performs all of the named roles. It's been working very well.