Yeah these little dongles sure sound good for the money, I'm definitely happy with mine! Only issue with the iBasso is it requires you to use the buttons to set the volume even when using it on a computer, since it doesn't support volume control through USB at all. Strange design decision, and with 100 volume steps it can be a little tedious, but it's pretty much my only complaint. It sounds great, so that's what matters most!

I just shared a very simple EQ profile in another comment, if you want to give it a try. I do like the Etymotics tonality with the treble boost, but oratory1990's preset also sounds good, just different. I haven't tried his Harman preset though, usually not a fan of these. But the Etys sound great to me now, I'm definitely keeping them, hopefully it will work for you too!

Edit: here's oratory1990's USOUND1V1 preset with some treble boost on top, it sounds a little bit different, but oh so good:

Preamp: -7.0 dB
Filter 1: ON LSC Fc 180 Hz Gain 3.0 dB Q 0.710
Filter 2: ON PK Fc 300 Hz Gain -0.8 dB Q 1.000
Filter 3: ON PK Fc 1000 Hz Gain 4.5 dB Q 1.300
Filter 4: ON PK Fc 1370 Hz Gain -7.2 dB Q 1.000
Filter 5: ON PK Fc 2500 Hz Gain -2.3 dB Q 2.000
Filter 6: ON PK Fc 8000 Hz Gain 7.5 dB Q 1.000
Filter 7: ON PK Fc 11000 Hz Gain -5.0 dB Q 5.000

Hope this helps!