Don't worry about the Helium supply, guys, this guy is working on a fusion reactor in this garage :D:
Maybe someone should look into creating a ship that's some sort of Helium/Hydrogen hybrid. e.g. Have an outer shell which uses the safer but less efficient Helium, but a inner shell of Hydrogen. Else maybe combine the two in inter dispersed gasbags. I think Helium as an inert gas would be pretty good at putting out a fire? So if a Hydrogen pouch caught fire, a neighbouring helium pouch, if punctured by the fire might help to put it out and contain the damage.
Alternatively create a molded, fire resistant/proof honeycomb structure that could seal in the Hydrogen in say, tiny little bubbles, a bit like the air bubbles in an Aero bar.
Wouldn't it be great if they could create slabs of a sort of fireproof polystyrene type material, full of small hydrogen bubbles, and if you let it go it would just float up to the ceiling? :) But would be relatively safe because the hydrogen would be contained within the structure. Anyway, maybe that's science fiction, but might be possible someday if it isn't today.
Anyway, I'd love to see big airships back. Fingers crossed.