In as much as the possibilities for compact transport and ease of deployment sound tempting, I think the risk / benefit of such a concept outweighs its usefulness. I would think that anyone who has ever been bird hunting would agree that an ultralight / hang glider would make as easy a target as quail on the fly to small arms fire. Just ask any FAC pilot from Vietnam about the risks, and that was done in acft that were flying 10 times the speed and altitude of an ultralight. When you consider that and the sensor and photo capabilities would be extremely limited, the amount of useful intelligence gathered by one would not offset the danger to the operator. Right now drones, satellites and ground sensors gather the info needed to accomplish the mission. The Intel shortfalls in the current OIF battlefields are due to Humint issues, particularly language and allegiance barriers, not aerial photo or electronic gathering.
IMHO, the loss rate / mission success with such a tool would be astronomical.
"Never trust a clean Crew Chief"