Here are my tips for you:
I heard the Modi / Magni at a recent meet. Unfortunately, I don't like the Magni. It has a lot of power for a cheap amp, but unfortunately, I think it's way too brittle, harsh, and generally bad in the treble area. The treble area is not revealing or transparent, it's just boosted and bad. Keep the Modi, but ditch the Magni. You now have a good DAC and a bad amp in my humble opinion. Sorry, but that's the way I hear it.
On to the music...
Proceed to HDTracks and download Sea Change by Beck in 88.2 / 24. That is one of the best produced and mastered albums in recent memory. Proceed to the track, "Paper Tiger." That is a reference track you can use from now on. It is fantastic and it should sound fantastic. Unfortunately, I still think you're going to need a different amp to hear it in all it's glory.
Congrats on the Alpha Dogs! I have not heard them, but I'm definitely interested in them. I'm sorry to inform you that in my opinion, not all of that Schitt turns to gold. I have a feeling you have made a very wise choice in DAC and headphones, but a poor one for an amp. That's just my opinion, but the way I see it, you're 2 for 3.