More iems or a DAC?

I currently have several budget entry level iems, such as TRN Conch, KZ Castor Bass, CCA CRA, CRA+, Chu 1, KZ HBB DQ6s. I mostly listen to music through my macbook air m1, just sometimes on my phone (iPhone XS Max and Samsung Note 20 Ultra).

I've been looking for a DAC specifically the Fiio BTR15 because it's bluetooth capability, but I also looking at another pair of iems such as Kinera Celest Ignite Beast and Dunu Titan S2 because I like how they look.

I listen mostly pop, ballad, citypop, kpop, jpop, jazz, RnB, sometimes rock and instumental, rarely metal, edm, or rap. I Currently like listening on my TRN Conch, CRA+, and the Castor. Those three are my go to when I want to listen to something.

So, with the current lineup, is it better to go for the Fiio BTR15 or just grow my iem collection even more?