Hello,
Did I ever mention I love Modern U? 🤭
For me, the soundboard microphones make a lot of difference. Without those, I'd also find the sound too "thin" or perhaps "metallic"/bright. Which makes sense: when we crawl behind a real upright we also listen to the whole package, which includes a lot of wood.
The soundboard microphones, properly balanced in the mix, bring in a lot of warmth and oomph. Again, for me this part of the sample set is a huge contributor to Modern U's excellence.
Be sure to try that out, if you haven't already!
Cheers,
HZ