Since we're in a sharing/caring mode (lol), I just discovered that you can send MIDI to the VEP plugin, and return audio to the same track. I.e., you don't need separate tracks for audio and MIDI! I've literally wanted to do this for a decade...where you are using VEP, but have just a single track on which to do both your MIDI and mixing. Here's how to set it up:
1) Set up the desired number of MIDI tracks, each which send MIDI to the VEP plugin track (for example go to the VEP instance and use Reaper's shortcut "Build 16 channels of MIDI routing"). Then on each of the MIDI tracks' Routing dialog, enable the check box "Master send."
2) On the track on which the VEP plugin is hosted, create Send routings that bus the VEP instance's various outputs to the corresponding MIDI tracks. Example: if a MIDI track sends on MIDI channel 3 to the VEP plugin, and the corresponding instrument in VEP sends its audio output on channels 5/6, route channels 5/6 back to that MIDI track. Also make sure the "Master send" checkbox for the VEP track is unchecked - we only want to hear the audio out of the MIDI tracks.
3) Now here's the trick: go into the Project Settings (Alt+Enter is the default on PC), and go to the Advanced tab. Check the box that says "Allow feedback in routing." This is important, because otherwise Reaper supresses the audio, because technically you have a feedback loop (MIDI track goes to VEP, VEP audio comes back to the same track). But, there's no risk because it's not an audio loop - we're sending MIDI out, but getting audio back. Still, you have to check the above option.
I attached a pic of how my routing is setup. A little legwork for the first instance, but then you should be able to just duplicate it for further instances (or save it as a track template).
Reaper is pretty insane in its routing capabilities 