If you're just complaining and hoping that DL does something to make your life easier, you're better off writing a letter to DL management.

The reality is that aircraft interiors have been redesigned to maximize seating capacity and in doing so, DL has taken steps to reduce weight and costs. Many solid cabin dividers between Y and F, which had mounting hardware for a changing table have been replaced by curtains. Lavs have been reduced in size to the point where turning around inside one, can be a tight maneuver and where there is no longer space for a person to use a fold down changing table.

I'd suggest that you start a thread in the Travel with Children Forum and find out how others are dealing with the problem.

As far as wifi is concerned, you could have used it to research the issue.