Hi doubleattack, the room emulation of WIVI is in my opinion not comparable to MIR. Moreover, if I want all the instruments to be convincing in the same room, I think I should play with dry and wet parameters in MIR.
The workaround works even for me. I noticed that the not fully loaded kontakt instances are almost a "feature" of kontakt. They load only the samples that are played by the project, the other are put off to sleep. When you play a note for the first time, it will be loaded by the instance and the second time it will be played; this is a way to save RAM, but I'd like to have the choice to use that or not.