Been trying to find such an instrument for a decade ..
Its not there, and probably will never come..
I think combining a Fantom 8 (same keybed as the rd2000) with an sd90 by Ketron is the closest you will get..
Espescially when Roland can deliver the new SNA2 voices to the Fantom in an update..

I find the Roland sound quite difficult to mix with the Geno# sounds..
They don’t blend well, almost every sound on my jp80 needssome compression and eq, or it will push the genos side to the background.
I guess the Roland sounds will blend better with the sd90