I record a decent amount of metal as well, 99% of which is stealth (even for bands that give the okay to record, it just doesn't feel like the right environment for a mic stand). FWIW, I don't feel like any of the mics I've used for metal shows are ideal. I really want to try the AT853 subcards though. The AT853 cards can give some good results, and some extra low end with the subcards would likely be great. The point of this digression is just that I don't feel like I have the "silver bullet" mics for metal shows.
Since choice of mics is highly personal, I'm very curious why you want to move to Schoeps. I know they are among the best quality microphones available, and a lot of people love them, but why do you think they'd be better than the CK63s for you? At least for me, I have little to no interest in Schoeps because, for the music I typically record, I am just not a huge fan of their sound. Again, that's just the subjective personal part though. Objectively they are top quality mics. So what is it that you feel is lacking in your CK63s, and what is it you feel Schoeps would bring to the table for you?