I have written the same on previous requests about PC/FX chains: why not simply "merge" them?
* If "normal" FX is inserted in ProChannel view, its interface (as shown already) can be in FlyOut. Plus specific "ProChannel" interface can be constructed, using the same technology as for FX Chain
* If ProChannel module is inserted into FX Bin view, its FlyOut view can be used as the user interface (or ProChannel view, but it is small and most modules have VST incarnations with normal UI in any case).
Why not use FX Chains in ProChannel? They are a kind of "VST hosts". Problems with Control Surfaces, no fast way to open wrapped VST UI, control elements are not bi-directional.
ProChannel was originally an evolution of Sonar "Filters", but it is grown first up to dynamic ordering and than up to general FX BIN. Its "dark side" is just historical, there is no longer anything special in ProChannel module compare to normal FX, arbitrary (3d party) modules are there, the order can be changed, etc.
CW will not loose "proprietary character" of ProChannel with such move, those who like ProChannel view (which is nice in Inspector and Console) will prefer modules with special (ProChannel) tiny UI.