I typically run a "Fake" money-site on my 301s for around 2 weeks. During this time I flesh out the link profiles with some fresh stuff.
I even go so far as pulling link reports on the expired domain, and building links to those links. I like to try to "Recontextualize" them a bit. (Building relevant anchors, etc, to the original links.)
THEN I 301 it.
I've also had great success doing what you say, and setting up a money-site on an expired domain. I generally do the same thing with the existing backlinks at that time.