The CK100 is similar on treble, the CK100 Pro is brighter and more analytical. It's also not in your face than the CK10 and CK100 and doesn't do sense of space as well.
As far as IEMs I own that I consider better than the CK10, it's the Blessing 2 (super tough to beat on a budget) and the UE18+ (I have v2 molded in a universal format and apparently v3 is not well liked). The best IEM I own is the UE18+. There's a slight aggressiveness that the CK10 has that nether of these have.
Although people like to hate on the Shure 846, it actually has some of the better higher frequency detail in the IEMs I own, but in a way that's not excessively harsh or analytical. But they also throw a lot of bass at you too, and it's somewhat loosely controlled bass too, even amped. You can tune it with filters between warm and bright. Tonally, it sounds like it was originally configured warm as it has the most consistent response though the frequency range. And the the other neutral and bright filters just deviate from that. It's one of the few IEM I have with really good level of detail of you're aiming for that while not being offensive. It's a very good, slightly imperfect IEM. It feels like a lot of R&D time went into it, time selecting and tuning, but then the end result wasn't quite right. It's weird. You start listening and instantly recognize the work put into the sound but also realize it's also just a little bit off. It might have been the drivers they had available at the time of development and the intended goal of the product. It's a product that needs a modern refresh. That's really what it needs, a fresh look at drivers and tuning and make a V2 of the product.
However, I'm curious if some other products might do better. I still want to try the Moondrop S8, and I'll probably pick up the new Monarch MK2 early next year. There's a LOT of products I haven't tried. I've leaned pretty heavily on crinicals IEM list for a lot of my modern purchases and basically grabbed everything good on it sub $1k that looked interesting. I was only disappointed by the IER-M9. It's technically quite good, but it's not a product I want to listen to over other stuff. He also ranks the SE846 kind of low, and I think it's better than the ranking shows. This is especially true on build and construction. I don't own a better constructed IEM than my Shures. But the guide has steered me mostly right. There's just a LOT of IEMs.
For the closest option to the CK10 in tone and character, I'd point you to the Blessing 2 and the UE18+ (specifically v2, not v3), two price points for two very good sounding IEMs that I consider are similar in character but holistically better to the CK10.
