Coming from someone who doesnt know anything about Vienna except the special edition products, as I understand it, the dimensional products are offering a more human sound, a bit more flexible and less mechanical. I imagine they really shine with instruments pro...
I wouldnt be using the dimension products if I needed range, Id be using the solo instruments. I dont disagree that the range is somewhat limited, but, remember that while even high schoolers can hit very high notes (I know I could, back when I was in high school, I played a special line that was written very high for the trumpet for the star spangled banner to add some flare to it). However, when we tried to have two of us play this same part, it sounded pitchy, because while we could actually hit the notes, it wasnt always in tune. With a solo instrument, thats fine, its not so obvious, but with 2 instruments, if they arent in tune, it sticks out like a sore thumb. Also, higher notes have less give on how out of tune they can be without being noticeable. This is why flutes, piccolos and trumpets in particular have to make sure they have a tighter omniture than say a tuba or trombone player.
While I may not have experience with Vienna, I do have experience with every instrument. I can play every major instrument in a band or orchestra, maybe not particularly well on a professional level, but I can play them all and have experience performing in large shows on nearly every instrument.
Perhaps the range is somewhat limited, that is precisely why youd use the solo instruments and double up on them (maybe you can make the special edition 1 or 2 brass work, and since you already have some of them, they would make those two extremely cheap). I dont know what kind of project you are working on, but my experience is, other than the limit on the articulations, the special editions sound just fine with a bit of eq and reverb.
I just dont think youll get a realisitic performance doubling up on solo instruments. Like I said, 1 player might be able to hit those high notes. Now have two of them hit the higher notes together and it will sound pitchy.