Been listening all night. Don't want to stop.

[ogs]

SHD studio would be excellent with the Reactor Custom as it has AES/EBU capabilities. If one can get the Custom as a private person that is...

Looks like the Reactor Custom might. These came to market just after I acquired the consumer Duo Reactor 900, I believe. However, they also have a smaller output rating (800w vs 900w). I don't see why an individual couldn't purchase them. One could touch base with Devialet Support to inquire.

With the Custom either AES/EBU for the SHD/Dirac or the Dante virtual ASIO sound card with Dirac on the same PC. If Roon is the player, SHD is the only alternative as long as Dirac is necessary (which I guess it is..). Both AES/EBU and Dante would most likely sound better than your current Toslink arrangement.
Finally, if RAAT ever comes to Phantoms that would be brilliant for your current Reactors, but you'd have to go with a different room correction software. Pity Roon and Dirac can't agree on how to work together. If there ever was a missed opportunity...