I'm more a fan of the 17 and 18, but I agree on the K Dark Thin. Can't go wrong with those, or the Custom dark, or Dark medium thin. I also probably hear the same thing as you in the K Sweet line. I like the crash sound, but there's something missing.Personally I would go for a 19" (or 18" if I have to) K Dark Thin Crash. I seem to be the only Zildjian fan boy in the world that doesn't like the sweet crashes, they just sound like they're missing too much of their tone or something to my ears. Blegh.
But yeah, the 19 KDT crash has a lot of attitude to it, and has a powerful presence to it without having any "trash".
The 1931 and traditional bosphorus may be a little think compared to the K so maybe have a look at some of there other cymbals in the different ranges.Thank you , I will do that -