You're not wrong about one thing: you know what you like. And that's what you should be using, things that you prefer the sound of.

Great "audiophile" (I actually hate using this term) headphones aren't necessarily the best fit for gaming. Gaming audio seems to be work best when the EQ curve is distorted to ridiculous levels, highlighting and exaggerating particular frequencies that give you in-game advantages, but that would sound awful to someone used to "non-gaming" headphones when listening to music.

The DT770 is known to be a little on the lean and dry side. That takes some getting used to. Your brain has to be adjust (and this takes time) from the overly sweetened / salty presentation of a gaming headset. Once you get over that adjustment period, you might grow to appreciate the subtlety, which will help you notice all sorts of little details that might have been hidden by the way a gaming headset is tuned.