I would *much* rather have the non-dependant stuff, of which there is a whole lot, built as separate packages. Wherever the source comes from, I don't want to have to rebuild a lot of cruft that isn't actually crucially out of date, just to get a reasonable kernel. If I rebuild my kernel on Linux, it's something like 30m. If I rebuild the DEBs for all of the basic utilities that one could imagine might interact witht he kernel (I don't have access to see what buildworld does on NetBSD right now), it could easily take hours...
hmmm. my celery400 lapdog takes about 2.5h to "make build", which builds all the userland, but not a kernel, and not distrib media ("make release"). that takes about another 1.5 hours (on i386) cuz it builds so many kernels (most other platforms only have a couple of kernels to build.) as far as packages of netbsd tools -- we (netbsd) are planning to switch to using the pkg_* tools for the base system sometime soon. the sets lists have had info about what package a file belongs to for some time, and you can see this info in src/distrib/sets/lists/*/* -- these files have a simple format of "filename setlist". i dunno if that will help at all for what you're doing, but i thought i'd meantion it anyway.