Sounds like a great option. I’ve deliberately held off on a tube amp because I know I’ll just want to roll tubes once I have one, and I can’t dig any more of a money pit than I already have 
What I am very keen to try is a tube DAP, because of the glowing praise given by @Torq and others on the Cayin N30LE. Cayin is releasing a cheaper version of it next month and I plan to give it a whirl.
Then when I make a fortune, I’ll just go straight to an endgame 300B amp and be done with it 
I’d not start with DAP tube amps, as they are a pricey relative to conventional amps and/or power limited versus a regular amp. To minimize your exploratory costs, go with a simple design such as the Bottlehead Crack or others like it. It has only two tubes, and no need for finding and buying matched pairs. (Matched pairs often cost more than two unmatched tubes of the same model.)
You might also look into a tube buffer stage, as they (1) are modestly priced, and (2) can be inserted between the DAC and any solid state amp. They can be used for speaker or headphone amps, and become functionally similar to a tube hybrid amp.
I bought a Nutube buffer evaluation board and built a sandwich case. No tube rolling possible with the NuTube, but it has four settings, and each channel can be tweaked independently. It’s educational if nothing more.
I’m going to get pedantic here, but the big difference between a tube buffer and a hybrid is usually the design of the output stage. Most good hybrid designs either use only moderate local feedback on the output stage or no feedback Mosfet output stages.
Most SS headphone amps that advertise low distortion numbers heavily use global feedback.
Feedback isn’t inherently bad (and it’s necessary in most SS gain stages), but it does change the overall character, and the limited use of it, for me it’s one of the reasons tube amps sound like tube amps.
But I don’t listen to tube amps for the added color.
Tube buffers can be a good way to add some tube color to a system though, if that’s what you’re after, and if I were getting back into 2 Channel, I’d be tempted to go tube Pre into SS Power (though It would have to be the right SS power amp) rather than all tube, the mere thought of having to change the 16 tubes in my current Power amps makes me cry.
I said “similar” and “tube hybrid.” I’ve messed around with running headphone tube amp LINE OUTS through my speakers. The tubes are absolutely audible, and make the SS amp more holographic/harmonic.
Are they as good as true tube amp? Well, it depends on your taste and the quality of the amps involved.
Hmmmm. I seem to have gone through that - Dynaco PAS-3x into Tiger mono solid state amps. That would have been college student SOTA in 1973 or 74. AR 1a turntable, Shure v-15 Type III (improved) cartridge. And that’s when i got the modded Rectilinear III Highboy speakers I still use. Wife upgraded as many of my parts as she could over the years.
So, to the point about the gear chain, my Geshelli Dayzee DAC just showed up today. It has the same AKM chip as the E70 Velvet I had and sold off but 2 of them, one for each channel, and it has a very similar smooth sound, very tiny bass boost maybe, and no hash or harshness to be heard. I got to try it out with the stock op amps, and because of a little miscommunication, actually ended up soldering in the Sparkos SS2590 Pro op amps because the DIP8 to pro adapters didn’t fit. The difference with the pro op amps vs the stock is absolutely staggering. The frequency response is unchanged and was already really good, but the sound stage is definitely noticeably enhanced. This is true through the WA22, WA2, and Violectric V222 equally. They all sound different, but the soundstage is radically better with this implementation of the AKM 4499EX on all the amps I have tried it on. On The Memory Remains by Metallica and the V222 through the Focal Clear OG, it felt like the drums were projected a bit forward and high - verticality varied across the different toms, but during a fill it seemed to make an arc from above my head to slightly in front of me. I was surprised to notice this. With all that people make of the soundstage from headphones, it really seems to me at this point that source gear (at least for how my brain understands spatial information) is at least as important if not more so. I really think with either the updated Ares or the Dayzee, the HD600 sounds like it has more sound stage than the 800 S did with the E70 Velvet… It seems a little less dependent on amp, but it does seem that the OTL SET tube amp might win out slightly over the others, but I am not ready to fully commit to that statement yet. So strange how all of our ears and brains are a bit different, but how fun to play and learn and rock out in the process!
I’ve been having a similar amount of fun with the Geshelli Archel 3 Pro amp, with those same Sparkos pro op amps. The soundstage comes close to, but still fan’t really touch, that of my Pendant SE (with the Schiit Gungnir as a DAC btw), but in many ways I actually enjoy the sound a lot more. The bass is well defined, textured, and reverberant, the mids have body and weight, and the highs are detailed and exceptionally smooth. And the soundstage, again, is impressively spacious. It’s probably not on the same level as your Dayzee DAC, but even at a lower price bracket, it’s clear that Geshelli and Sparkos are doing something right!
They are?
You’re not talking about the “N3 Ultra” are you?
If you are, while I’m sure it’ll be a lovely little unit for <$600 (the N3 Pro was), it has almost nothing in common with the N30LE. It’s an evolution of the N3 Pro.
How are the shock absorption and microphonics, and the anti- RF interference capabilities of tube DAPs?
Can’t speak specifically to the DAPs, but I have the Tube Mini dongle from Woo Audio, and it is best used in a stationary position away from any devices with active cellular signals (WiFi not so bad), or it will absolutely pick up some interference…
Hmm yes I did mean N3 Ultra, I thought it was going to be similar in terms of offering the same tube classic mode that is so loved on N30LE. I understand that the Ultra is not using the Korg Nutube though…