How important is timbre to you? The TRN BA5 sounds like what you're looking for, but their timbre is a bit mechanic.. Tonality wise they're neutral and dry, with bass that's probably too tight and fast. It's an all-BA unit.
I just ordered the TRN BA5. I was looking for a more neutrally tuned IEM and it was between this or the Moondrop SSR. Decided to go with the all-BA unit as I’ve never tried one before. Hope it doesn’t disappoint!