I see that not too many tube pres offer balanced inputs, any thoughts?
Among the three noteworthy alternatives, i.e., 1. Freya, 2. RP-7 and 3. VTL TL5.5 Series II Signature (2013), TL5.5 II Sig. has the best impedance matching feature.
https://www.stereophile.com/content/vtl-tl-55-series-ii-signature-line-preamplifier
This trio has received high praise from Stereophile, but impedance matching deserves careful consideration in the DAC → preamp → amp chain. The Freya has a low input impedance, while the RP-7 has a extremely high output impedance at low frequencies.