Tbh I wish I knew, but I'll try different approach. Every time I think I know what I want, turns out that's not entirely it once I hear it. Let me know if this is helpful.
I am mainly looking to have 2-3 main IEMs. Current keeper since it's custom is my EE LX. Next IEM I think I am searching for is a musically engaging warm neutral. I really enjoy U12T's bass, but overall U12T is just a tad too relaxing. MEST is too aggressive for what I am looking for and mainly favors rock which is not the genre I generally listen to. Andromeda is not quite as technical as I like at least compared to the 1.5k to 2k+ IEMs that I have tried. Atlas is meh, but I enjoy original Vega from what I remember. LX and IER-Z1R to me has a balanced sound signature. I don't generally gravitate to straight warm headphones/IEMs with the exception of Meze Empyrean but I do love large quantity of bass (so I usually take LX and bass boost it). Although Dorado 2020 seems a little enticing for some reason (but haven't heard it). Just received VE Elysium and mids sounds really nice, but not sure yet how I feel about treble and bass. I do like the little dip in the upper mids that the Andromeda and U12T has.
I primarily listen to electronic, edm, pop, rap, rnb. Occasionally instrumentals and rock. Some artists I enjoy are Billie Eilish, Lorde, Sam Smith, Kanye West, Linkin Park, Alicia Keys, Daft Punk, Zedd, Old school Dr. Dre, Dua Lipa, Hans Zimmer, Daft Punk, Scott Bradlee's Postmodern Jukebox, Taylor Swift, Glass Animals, The Weeknd, Justin Timberlake, and more.
Edit: I did enjoy IER-Z1R, but I wanted more bass rumble at the time lol. Also heavy for me. I am considering rebuying it now that I have learned a lot since I last tried the IER-Z1R. Out of U12T, Elysium, MEST Mk2, Andromeda 2020, I seem to be enjoying Elysium the most so far.