re: probably a dumb question, but about landing probes on low gravity objects....
The mission as it stands, already descoped to the tune of a laser altimeter and magnetometer, has already blown its initial budget, the idea of adding even the most simple lander is way beyond what's possible given the resources available.
You're right, they're comparatively easy to land on, but still not THAT easy. Unless you wish to put your main spacecraft on a direct impact path before deployment ( like MEX or Galileo ) then your probe has to have attitude control and an ammount of delta V ( so it becomes as complex as the Deep Impact impactor probe )
Doug