Deep Expressor was only in the beta, before the 2.5 release. It has some simularity with some Roland hex cosm fx yes ( I do own a lot of that stuff too…), but I discovered this kind of sound more by fooling around with midi and filters, like 10 years ago. Gladly I could use this experiment lateron. We’ll introduce it lateron officially, you managed to “steal” it out of the beta, so you can use it anyway for now, just copy the patch to a new one if you need another patch with it…
When MIDI Guitar is loaded into a host like AUM, it is natural to have the synths loaded in AUM, not inside the MG IAA plugin. (this is simular to desktop situation)
The loading of AU’s inside MG is targeted on having a simple host, remote controllable, with a very guitarfx kind of setup. For many, using a extra host is too much hassle.
For complexer setups, there is allways AUM and AB, but we can not really guide users there: there is just so many thing to know about e.g. the differences between IAA and AU, if you want to use it succesfully, especially with midi program changes for recalling patches.
Our AU option just offers the simplest possible solution to invoke a synth in a live setup.
MIX and MASTER would be good candidates for remote control, agreed…
The stuff that is shown in a host from AU plugins are “automation parameters”. they are not midi, but hosts often offer options to attach them to incoming midi. On desktop these params are the ones you can attach an envelop to in the track.