Generic external synth VSTi

This would be a generic VSTi supporting any external synth that has its own MIDI and audio interface. A user could insert this VSTi as a simple instrument track or a combined midi & synth track, including multiple MIDI tracks, even multiple audio outs, and use it much as a softsynth VSTi. Apparently there are some such VSTi's that are dedicated to certain synth models (see below). But does a generic such thing already exist?
 
It works by sending MIDI to the synth and receiving the associated audio directly, then injecting it into the associated synth track. The VSTi would need its own path, or pseudo-path, for receiving the audio and sending midi. This could work if:
1) the synth is connected to a midi port, including one port of a multi-port interface, or has it's own USB MIDI interface.
2) the synth audio output has its own audio input or uses channels of a multi-channel audio interface already managed by Sonar.
Requirement 1 is typical; just don't use any MIDI thrus on that port.
Requirement 2 needs Sonar's help if the device is connected to a multi-channel audio device managed by Sonar, and may or may not be easy if the device has its own audio interface separate from the one configured for Sonar's sole use. (E.g. sample rate mismatches)
 
At the moment, a user can configure a MIDI and an audio track and try to manage them together, but Sonar knows nothing about the association between the two. So a user might be able to group the solo and mute buttons, but freeze and bounce don't quite make sense. A simple instrument track is not possible. (some would applaud this ).
 
A VSTi usually has a big panel with controls for editing presets. This would not be practical for software that needs to work with all external synths. However, it would be nice if there could be a way to let the user configure some common operations, like sysex commands to set synth modes, or bank select methods not supported by Sonar; but the patch list could use the master.ins. Maybe even some controller mapping, e.g. envelope to controller or envelope to sysex to get at some parameters in the synth. Let some synth owners generate profiles that could be loaded into this generic VSTi by other users.
 
This FR was inspired by the M3 VSTi referenced in this Sound on Sound magazine article here: https://www.soundonsound.com/sos/apr09/articles/sonarworkshop_0409.htm. posted by Jesse G in the Sonar forum. Craig's article says "... many newer hardware synths (particularly models from Korg) are designed to function as if they were VST plug‑ins within a DAW such as Sonar ...". And the article goes on to use the Korg M3 as an example.