Personally, I find that the most annoying aspect of IEMs is how the trebles can and often are pure chaos. At one point, all the cheap stuff would have some 10kHz spike that made people believe it had detailed trebles, but it also made cymbals and others similar instruments sound like you just dropped a few spoons on the floor. It's pretty hard to get nice upper range in IEMs, and it's even made harder by how slight changes in insertion can change the upper frequency response in a big way. Sadly, the amount and tonality of the "pschhhhhhh"(totally super technical term) are going to be heavily impacted by the upper range. EQuing is tricky and borderline dangerous IMO, because it's easy to start pushing for a dip we almost can do nothing about with EQ, and then have that shift a little in frequency and start killing innocent air cells in the ear because that particular nearby frequency is now way louder while still being in an area we're not all that sensitive to (it destroys us, but we don't really feel it).
I very much enjoy drummers who show subtlety over speed and violence. It's a general drummer thing for me and not specific to cymbals. For rock, hard rock genres, where the guy must get into it, I noticed how I often lean toward those who don't record their drummer very loud relative to the rest of the band. Most Iron maiden recordings, for example, I might have been a total fanboy anyway, but I think how they mix things played a part in how much I've loved/love them(Bruce>all). The drummer is still all here, but not Animal here.
Edit because I reread my post and both Godzilla and I had a stroke. Too much autocorrect trying to make sense of my poor typing.