Yes, I know, pdisk has an option to rearrange partition numbering (haven't
compiled it for NetBSD, yet). Somewhat dangerous with OS'ses installed,
however. It's just as, when I set up NetBSD, had to use pretty old HD SC
setup which doesn't allow slice renumbering.
Physical location of slices was well considered: swap first, 'fastest OS
last' (or, wrt MacOS, 'least important last'). So less ressource intensive
NetBSD actually resides behind Linux on physical HD sectors that offer
(slightly) slower I/O.
On the other hand: following your argumentation that NetBSD-mac68k
should reside on first OS slice (Mac partition #3 i.e. /dev/sd0a), you'd
expect other OS'ses boot machinery to offer more flexibility than NetBSD
Booter does. What if there were AU/X on disk which also relies on sd0a
as root? PC style maps use flags to assign partition types, so FreeBSD
wouldn't even dare to touch a NextStep slice. But with Apples, alas, all
non-MacOS systems use unique & confusing Apple_UNIX_SRV2 identifier.
Torsten