[FR] Most of the coding for this already done...

It says, just download and edit/adapt it, and build into your host…! Then third party devs can enjoy added benefits INSIDE the host:-
http://www.presonussoftware.com/en_US/index.php?id=developer

…one example of which can give visual feedback for the user, demonstrated by FabFilters latest Pro-C2 compressor update, released yesterday. Here’s a screen-grab from a KVR post…
http://www.kvraudio.com/forum/viewtopic.php?p=6219529#p6219529

See that little yellow ‘gain-reduction’ line in the Kick channel meter window in the mixer…? It now responds to the FF plugin…! (and not just Presonus own internal plugs). Nice.

(BTW - Cubase does have these ‘gain-reduction’ meters - but only available in the ‘Show Meters’ section of the MixConsole, not in the channel fader/meter; and only works with ChannelStrip activated comps…)