Airships would make quite decent transports, but only within an atmosphere. They can carry more weight than a comparable plane, making it possible to have both cheap budget flights with lots of people packed into a single airship, or luxury "air-cruising" for those with a bit more money to spend. They're not practical for space launches though, as the envelope needed to encompass the lifting agent (or lack thereof) would have to weigh more to not rupture, but that would make it too heavy to get far enough away. They could have a lot of potential for probes and landers going to places with a thick enough atmosphere, working essentially as very low-flying satellites, potentially avoiding surface problems a conventional lander would have (such as cold geysers). One idea would be a probe suspended below a balloon, which could explore gas giants up close, bypassing some of the magnetic field effects that make it difficult to examine gas giants from a distance. The Hooligan Airships parts are not particularly realistic, by the way. I still like having a blimp-probe on Laythe.