Use Layer output/ Mix outputs as master layers

One of the big limitations of the visualfx is not being able to use any if you need to keystone and having to duplicate the keystone parameters to every layer that contributes to a keystoned output.

Would it be possible to implement a slightly different sort of uselayer which took the output of a layer as the source for a new layer so allowing the chaining of effects.

Could the mix outputs also be integrated into the architecture as layers 11-14 effectively giving them the functionality of master layers; so keystoning other visual fx and color fx could be applied to a mix. Implementing master layers in this way would not require any additional or special dmx parameters; just assigning 4 more fixtures.