Well, somehow we got stuck keeping the existing OO approach since it was already there; sometimes it's hard to get a view from the outside by yourself...:/

My greenfield approach would have been something like

if ($config->hasFeatureA()) {
// show feature A or put it into the container
}
[download]

(Depending on the project and just to get the idea).

Thank you for your answer and sharing your point of view,
k