jangofett,
In my opinion Modi Multibit and Jotunheim would be a bit overkill. Don't get me wrong. If you have the cash to put in now, and you think you might be getting farther into the hobby later on with more headphones, then go for it. Those components are well worth the price.
However, (and Jason has said something similar himself in this thread) it's my opinion that the most important component for the sound is the headphone. The HD 700 is one of the better models you mentioned I believe, and it can be found well below $450. I think using it with a $650 stack (Mimby + Joty) isn't going to give you the best bang for your buck. Swapping out the Mimby for a Bifrost multibit will make the discrepancy worse. And this is all even more true for the less expensive headphones you mentioned. If you do want to spend this much however, I still think Mimby + Joty is a better sounding (though less uniformly shaped) stack than the delta sigma Bifrost + Asgard 2.
So there are a couple other options:
If you like the idea of something balanced, I'd go for the Jotunheim with the built in DAC option. At $500, it will be fully balanced (including the DAC), which is pretty awesome. And as per your previous question, yes, it will be noticably better than a Magni/Modi stack (in my opinion). I think the people in this thread sometimes underestimate the DAC card in the Joty, just because it's not multibit. This setup will only accept USB sources. I personally really like this option, especially taking into account how compact and nice the Joty is as a product.
If you really want to try out Multibit, then I would suggest you get the Modi Multibit with either a Magni Uber or a Vali 2, depending on if you like tubes or solid state. The total of this stack is $400 - $420. More in line with the kinds of headphones you will be using. The upgrade to Asgard on the amp side is another option here, but not worth the price and size difference, in my opinion. This setup will accept toslink and coax as well as USB, if that's important to you.
That all being said, I personally think you shouldn't underestimate how well a plain old Modi + Magni Uber/Vali 2 stack will work for you. Especially if this is your first investment into headphone electronics. Don't convince yourself that you have to spend a fortune to get good sound. A Magni Uber or Vali 2 with Modi (USB only, steel enclosure) will only set you back $250 - $270, and it might give you everything you're looking for. If you need more digital inputs other than USB, or it will bug you to have a steel enclosure on your DAC, get the Modi 2 Uber, bringing the total to $300 - $320. Still very reasonable in my opinion.
Good luck on your journey!
As a side note to everyone else, writing this post has made me realize how many amazing options there are in the Schiit lineup. There are so many good combinations for so many different price ranges. Also, and I know this is probably impossible or stupid for some reason, but it would be amazing if there was a balanced multibit DAC with discrete outputs, but using the same chip and comboburrito filter as the Bifrost, priced between the Bimby and Gumby (maybe $900 - $1000??). This would pair nicely with Joty, and it would bring much of the benefits of the Gumby to those that simply don't need anything more than 16 bits (like me
. But maybe the cost would be to similar to Gumby to be worth it. I have no clue lol.