So what is the difference between Rack instruments and Track instruments?
Is there any benefits for using the first one (Rack) when it comes to VEPro?
The only difference I know of is the feature Save Selected/Load Selected does not work with Instrument Tracks. How often do you use that feature? 
I think over the past several years Instrument Tracks has evolved to the degree where there isn’t much difference any longer, except your desired workflow and how it integrates with apps such as Kontakt or VEPro. If you don’t get enough VEPro replies here you might try VI Control.
Okay I will ask at VI Control.
MAybe this will be useful too: Track vs Rack Instruments in Cubase Templates, a Different Approach - YouTube
Yes that was a really smart move.!