If I understand what you are saying is that you have a board with a dynamic shape fill on top layer and bottom layers,(1 and 4) and 2 inner layers (INNERLAYER1 and INNERLAYER2) for signal paths?
You can stitch these 2 shapes together with vias in a pattern that will cover all your area equally. Just run your traces (clines) around them. Also you can used an imbedded via on your pads if need be. Also are you using hidden vias? Not real good idea, but if you can avoid it do so. Costs and problems go through the roof sometimes.
This should be and easy build. Just place parts first and route it, then do your dynamic shape. see if theis works for you.