EDIT:
(*) added smth in terms of number of devices on MADI bus

€1xx more and get UFX+ to get MADI and by this USB3, Thunderbolt, then get a MADI capable Mic preamp.

MADI offers you more advantages
- distances between devices of up to 2km (compared to that ~10-15m with ADAT/TOSLINK)
- (*) MADI supports up to 64ch which gives you higher scalability and reserve in terms of
   a) # of devices that you can connect (i.e. @44.1/48: 8 preamps à 8ch)
   b) # of total channels
   - 64ch @44.1/48 kHz (single speed)
   - 32ch @88.2/96 kHz (double speed)
- MIDI over MADI is a nice feature which makes separate MIDI cabling unnecassary for remote controlling the preamp
- Some RME Preamps (like XTC and 12Mic) can be integrated as AUX device into TotalMix FX
  by this you can remote control things like Gain, PAD, etc ...
  and digitally store / restore settings in TM FX along with the routing

All in all its a fantastic combination and allows for a high operational comfort and reliability. Another big advantage of MAID optical cabling is, that you have dedicated fibers for audio which results in lowest latency and highest reliability.

Ideal would be a combination of:
- UFX+ and Octamic XTC or
- UFX+ and 12Mic (which also allows for AVB operation and can be managed additionally by browser over network)