You raise big questions about a starting point that is just a request for technical information on samples. I do not know if you are really responding to me or if this is an opportunity to talk about something that is important to you.
I have listened all my life (which is starting to be long) to orchestras, on record and live. I read Berlioz's treatises at a very young age, Widor's suite, then Rimsky-Korsakov's orchestration books. I am also friends with sound engineers dedicated to large orchestras, whose work I follow closely. I think I have an ear for the balance of instruments (my initial question follows my listening to the trumpet samples, too powerful for my ear, despite the natural power of the instrument). I never sought, however, to be played by an orchestra myself. The thing is inaccessible to me (and I have not worked very hard in this direction). I prefer to write for small sets, it's more realistic. But at the moment, I'm writing for a big band, which is a medium-sized orchestra (and more of a studio orchestra, so with strings). So I'm writing for a larger set than usual. This is why I return to full sections. I often work with Spitfire's BBC Pro for scale models (Spitfire's BBC is very well balanced: it exists), but I needed the saxophones and Spifire doesn't. So I turned to my library in Vienna. But I found that there were volume inconsistencies. But hey, we're not repeating this discussion. It is best to check and adjust yourself in any case.
However, I would like to come back to one of your comments. The one where you talk about building in virtual, without remaining fixed on the rendering of real instruments. You open the door to a very broad, very interesting discussion. For my part, that's what I do three-quarters of the time. I'm not interested in imitating the orchestra (my current job is to compose for a real jazz orchestra, so all my questions concern the creation of a model in support of a score, for decision-makers who do not read all music on paper) - except in the case of models. What interests me, however, is what virtual instruments can give that real instrumentalists cannot. Here, we open up remarkable perspectives.
For my part, what interests me more, in fact, is the mixture of the two, real and virtual. I composed a first project of this type a few years ago. : NOVIAUS TANZ, for violin, cello, virtual violins & virtual double bass. The score for violin and cello is recorded by two members of the Molinari Quartet. The rest is built by me in Pro Tools, with VSL instruments and without any connection with the reality of the instruments (while remaining plausible however). I give the link here for those who might be interested as a form: https://metis-islands.bandcamp.com/album/noviaus-tanz-for-violin-cello-virtual-violins-virtual-double-bass
I have been surprised for a very long time to see that most of the demo works presented on the Vienna site are orchestral imitations. Nothing for the virtual creation (or I'm wrong: it's been a long time since I have not peeled the site). Nothing for what is hybrid, like my example. Great discussion!