Thank you for answering.
Yes, the way you're handling the portamentos is great, that way one can create the required articulations within Dorico (not sure if it's possible in Sibelius in such a way).
I guess these would be tools for users who are fine with tweaking and creating their own expression maps within the notation app (normally people used to DAWs). The benefit to having Noteperformer able to access these articulations is that the user doesn't need to have extra staves for the instrument to access the articulations nor have to load the Spitfire Player twice (or Kontakt, Synchron, or whatever), saving on resources.
So, if you feel like adding CCs + certain values is an easy thing for you to do, it'd be amazing.
I use the BBCSO tenutos and marcatos for certain phrases or repeated patterns like chords being played in quarter notes. On my end the tenutos seem to have a release, though. And the marcatos for the woodwinds, brass and solo strings have round robins and more than one dynamic layer.