I love the Helios. It softens the highs and lows without you doing anything. (Oh golly gee, “analog”-sound.) I use this about 90% of the time when I am tracking into my Apollo, and frequently as an insert for virtual instruments. It’s like I’ve got a Helios board. Kinda sorta. The EQ gives you just enough subtle control and… [see the hint].
Experiment with the Line vs Mic input. You can get right on the edge of that cool vocal distortion (oh, I mean “saturation” lol) that hits only on the loudest transients.