Currently in a Web Map, it seems not possible to have full control over the drawing order if there is a mixture of REST services with and without the layer numbers specified. Those layers with a layer number specified have to draw over and those without a number specified. This may seem like a small problem, as one could republish the layers in new REST services to eliminate this. However, REST services creation takes time and hosting them uses server resources.
Does anyone have a trick for controlling this?