I seem to have phrased the insert effects priority a bit wrong, sorry about that. I wanted to put emphasis on third part insert effects, Cubase insert effects being secondary. But I have just now found out why my third party plugins did not work in VEP: 32 vs 64bit incompatibility, but I've solved that issue now, so I can use those in VEP. I can live with not being able to use Cubase insert effects, I'll just abandon them I guess. This way I would be able to use my master VEP as my main mixer. Thus I can remove the master VEP outputs that went to Cubase, which will definitely speed things up.
I'll then have to see how to set up the reverbs in VEP with buses. MIRacle versus Vienna Suite's Hybrid Reverb, no idea which would be better. At the moment I was using Hybrid Reverb sections for strings, brass etc. which each only had the early reflections, and the main output channel which only had the tail (so grouping of some sorts).
Back to the routing: However, even if I change the above, I'm still sitting in front of my main problem: the audio input plugins for my slave VEP. I'm not 100% sure I understood your setup. Is there a way other than audio inputs via Cubase to get the individual outputs of my slave VEP to the master VEP? Because as I understood the VEP master/slave principle, the slave VEP outputs go into Cubase, from within Cubase you route these outputs to the master VEP inputs (via audio input plugins, which is killing my asio performance - according to Dietz optimisations of Cubase that interfere with VEP). Once I change the above-mentioned, I wouldn't 'need' any outputs in Cubase anymore, except for one or two from my master VEP.
I don't see how grouping would help here, because I want to have each instrument of my slave VEP separate in my master VEP's MIR for perfect positioning. How do you send your slave outputs to your MIR instance?
Thanks a lot for your assistance in this matter!