Welcome to the community @robur44
That is a lovely DAC (from what I’ve read, I haven’t heard it myself).
SS vs. tubes for the VC is entirely personal - if you like the tube sound and perhaps want the opportunity to tube-roll, then there are lots of possibilities. I’d start by looking at the ZMF Pendant, given it’s in your price range. Offerings from Feliks Audio are worth a look or for an increse in budget ampsandsound (they make the Pendant but have several other fine offerings under their own name) alongside Glenn, DNA, Pathos, among others, will be worthy considerations but for increased cost (unless you buy secondhand, which I’d personally advise).
It really comes down to what sound you’re looking for and what you’re looking to achieve e.g., you might prefer the EL84 over the EL34 tube or a KT88. Or you might love the lushness of 300B’s. Alternatively, you might be seeking a very neutral tube amp or perhaps even a hybrid (like a Pathos Aurium).
It’s a similar story with SS, what sort of sound are you looking for? Something ultra-clean sounding like a THX amp, a wire-with-gain approach or are you looking for SS with a little more character, colouration, warmth, sweetness vs neutrality. E.g., a THX amp might not be your cup of tea because you seek a little more warmth in the presentation etc.? You may consider Class A designs to be preferable to Class D for your needs.
You’re likely to get more helpful recommendations (and general responses) the more specific you can be about what you’re looking to acheive. In a room of 10 VC owners, they likely all have different rigs and slightly different objectives. Personally, I like a warmer signature in my gear, I’m not all that interested in neutrality (in a purest sense) and I tend to gravitate toward a more euphoric and holographic presentation but not an overdose of this. I dislike equipment that I perceive to be sibilant, treble-peaky, sterile, overly analytical, or digital/hard in character.
Part of the reason I like warmer gear is that I listen to a lot of poorly recorded or harsh sounding music - more than 60% of my music collection is metal of some form. So, a little warmth in my rig goes a long way to make my listening experience more enjoyable across my collection - which is my leading objective, to enjoy my collection, rather than be limited to styles or recordings of the higest order. Your objectives might be manifestly different to mine.
Having said all that, the collective opinion is that ZMF headphones love tubes. Zach himself is a big tube fan and ZMF sell a tube amp. So if you’re worried about ZMF headphones pairing with a tube amp, don’t be! ZMF headphones paired with a GOTL, Feniks, Woo Audio, ampsandsound, BHC, DNA, etc., the consensus is extremely positive.
You might also be better off in the official VC thread, where you can get the attention of owners: ZMF Vérité C - Closed-Back Dynamic Headphone - Official Thread