So after doing some more reading, I found a post on a NetBSD mailing list where Chuck Silvers explains how he renamed a few VM related sysctl's (..the old versions are still used by OpenBSD, max values are hard-coded defines.. no knobs).
http://mail-index.netbsd.org/tech-ke...2/08/0006.html
I also found an early optimization guide written for NetBSD, some of the principles.. except for UBC (..not yet in OpenBSD, but has been commits lately) may still apply.
http://www.selonen.org/arto/netbsd/
If I understand all of this sufficiently, the kernel behaves differently depending on how the system is being used.. adapting as it goes along.. the services that knasbas utilizes aren't demanding large amounts of memory, so the majority of available memory is being reserved for other things.
I don't pretend to understand it all, because it's complicated.. using the above optimization guide on OpenBSD is
NOT recommended though, the defaults will most likely be quite adequate for your needs.
Good luck.