Even when using Rack Instruments, I have mostly stopped using VST instruments in their multi-timbral mode for synth plugins like Omnisphere. It just seems easier these days to use one sound (or set of layered sounds) per VST instrument.
However, I still use “songwriting template” multis in HALion, Kontakt, and Falcon containing 16 to 32 instruments that I use to quickly load a huge palette of sounds that I use to get down my ideas. I use similar multis for my orchestral palette.
Having to load this number of VST instruments at the start of a session would be a major buzz kill and defeat the purpose of be able to quickly pull up a batch of sounds to get my ideas down.
So I’m never going to get away from using multitimbral instruments. And that means I’m going to need to keep using MIDI tracks (and Rack Instruments) in Cubase until Steinberg changes the way Track Instruments are duplicated (so as to not create a new instance of the VST instrument plugin each time).