Reading threads like this makes me glad I’m a part of this forum. It’s rare to find a place where no one shits on other people’s quests for sound even though they may be on a completely different level of their exploration in the hobby.
Keep on keeping on guys. 
I think a lot of good points were made here. What I can add is that I’ve had a few “WOW” moments as I worked my way up in this hobby. That being said it was mostly, if not all, headphones or speakers, not amps or dacs, that gave me that WOW. First was my very first set of entry level open and closed backs, next was my first set of bookshelf speakers. Then I got the Neumann NDH20s and they “wowd” me in a way I can’t exactly describe because a lot of people don’t really like them, but they are perfect for my taste (although I admit the price may be a bit too much for them). The Elex “wowd” me in every way possible. The jbl 530s also “wowd” me in just about every way.
What I’m getting at here is, get yourself a decent amp and dac setup, and almost always put more focus on the headphone or speaker.
Coming mostly from car forums, I completely agree with this statement. It’s refreshing coming in here.
I agree, this is a great forum, filled with folks who are knowledgeable in their own experiences, helpful, never condescending, and alway courteous. Yea to all!
I love my Sivga 006 too… one of those great performers for the dollar. I put the Audio-Technica ATH-M40x in that class too, even more so with a ear pad mod. So, I was in the same boat as you, until I ugraded to a headphone amp… Curiosity set in 
So, now in similar fashion, I buy yet another bang for the buck headphone the Sundara.
I’ll drop my opinion on this question now. when you jump from $10 to $50 and from $50 to $100 and from $100 to $200 and from $200 to $500…and even from $500 to $1000, though to a lesser extent than the other price brackets, there are great leaps and bounds in the gains you make to your audio quality. after that it’s becomes more nuanced and one headphone will do a niche better than the others. so if you have the budget for that level of product, you can sift through and find what you like for niche reasons. this is for headphones. after $100 for DAC and amps now, it’s all about nuance.
the jumps in quality are very apparent in soundstage, imaging, comfort, build quality (comfort and build quality are really big things that go up when you pass the $1000 mark as time is taken to tweak), and such.
of course, as the prices go up, you also get to pick on nuances still, but they’re minor in comparison to the other factors.
I listened to some decent headphones…Meze 99, Gradeo GW100, Alara’s and then tried the Focal Stellia…headphones that are 10 to 20x the price of the others. it was apparent how much better they were in EVERYTHING…even against high end headphones like the Arya. however when I put the Focal Clear’s on…headphones that were half the price of the Stellia, the differences were muddied and it became more about the nuances.
Plugging a big Asgard 3 into a smol dongle DAC might be weird, so you might be tempted by a desktop DAC. 
Certainly so. 
Actually you can add one of two different DAC modules inside the Asgard 3, so you could get rid of the dongle for 99$ (or 199$).
I don’t know which one would sound better – of if you could hear the difference – DACs are what make the least of a difference in the entire chain (just don’t amp low-fi motherboard integrated DACs or something).
The 99$ AK chipset is probably your best option to get rid of the Dragonfly – the 199$ one is “multibit”, technically R2R? And might color the sound.
It really depends on you. Take me for example, I was, for years going up and up on the chain. Grados, then Hifiman He-400i, then a (for me very very expensive) MrSpeakers Aeon flow closed. I was then in the same mindset that you are in now. But then I “invested” in a Tin T2 and I realised I prefer it, the 35$ iem to my 800$ over ear.
So my moral of the story, expensive doesn’t equal better. Trying out all of the possible kinds of technologies and types of headphones and then choosing the one that you like best does!
That’s… an odd choice but, to each their own. 
My 30$ KZ AS06 are excellent too.
Maybe I still don’t know what I am talking about but : I have the jotunheim here with the 4490 dac card as well as my Asgard 3 with the multibit card. I prefer the sound from the multibit. I am not really sure if it is the dac or the amp that is the difference though… Both units have balls that drag on the ground though!! LOL!!
This works the other way around too lol. One day i needed speakers for my computer. So i decided to splurge and buy the Bose Companion 2 Series III speakers 100$. I couldnt believe how good it sounded. that started a journey for me. now i’m 8k in. Its ok i can pay it np, but you wanna be careful with this hobby. The costs stack up.