I think you may have drank too much eggnog. 
As far as total mix versus going through Cubase, maybe you are sensitive to latency. You won’t get a lower latency monitoring digitally when going through just the sound card routing. Once you add in Cubase, you add a little bit more latency depending on how heavy the project is and whether you have constrain delay compensation on and/or if Cubase direct monitoring on.
As far as monitoring in media Bay versus importing the sample, I think you have some mind trickery going on there. I’ve never experienced that. It’s different auditioning samples Click by click versus dropping something in a track and getting it leveled up with everything. Two different mental States.