Various systems need different amounts of space on the boot drive. This
is clearly spelled out in the installation specs. The question is
whether or not you will have enough disc space in your System Volume.

You say that you are only sending Spool files to the System Volume. I
have had a situation where a program went south and produced a $STDLIST
of over 20 million sectors before anyone aborted it. I have had
programmers build groups in the System Volume without knowing it (the
default is to build a group in the System Volume regardless of where the
account resides. You must  specifically build a group in the private
volumes.) Generally speaking a little extra disc space couldn't hurt,
except the wallet.

An other suggestion is put on as much memory as you can afford. This
will also help prevent bottlenecks. The 969 can take up to 3GB of memory
last I looked.

I hope this helps.