Since dCore is more Tinycore than Debian in what it needs kernel wise, I don't see a reason to use our own builds of the Debian kernel versions. And that would mean more builds, bugs, testing, etc that I honestly don't have time for. Any kernel build is going to have some bugs somewhere, we just have to live with what bugs are there, the bugs will just be different in another release.
We would have to build the Debian kernel version with our own config needs, the only difference in that is the kernel version numbers. But I would like to leave each dCore with a kernel version in the same era as the Debian release was as packages that have a kernel module build as part of their compiling like Virtualbox may not build against a much newer kernel version, I have seen that once.