My thought was really something more throw away - a small spherical probe, insulated with aerogel, with a battery, a small reaction wheel for orientation, a camera, and a low power radio.
Definitively, just a camera, a spectrometer, a short-range antenna, and a battery to power them for 6 hours or so. Something like the first probes, but miniaturized (and much much lighter). A few kilograms of mass budget, no more. Not sure if a reaction wheel would be the best in this case (those discs must be a bit heavy), maybe cold gas micro thrusters and a very small pressurized tank would do it.