Friend of mine is obsessed with airships, so I've been required to learn a few things about airships. The primary problem with airships is they're a stone cold bitch to land. Zamperini Field, where Goodyear lives, is a short drive from where I live... and Goodyear is generally inflated, tethered, and taking up about eight football fields rain or shine. That for a conveyance that will take like six passengers five hundred miles. They're also really expensive to fly. Cousin of mine flies hot air balloons for a living. He gets about $180 a head for a tourist up-down 1-hr flight (landing is also a bitch - he can only fly about 4 months out of the year). Think he pays nearly $90 in propane for each passenger. Compare and contrast: Airship Tours tried to make a living in LA at $1000 a seat but lasted only a couple years. Finally, we're running out of helium. Hot air blimps do exist (my cousin has one) but to do it right, you use helium. Even with helium you get spectacular crashes. Pretty sure the entire WWII dirigible fleet of the United States crashed. (I was close- the Los Angeles survived to be dismantled). So you're left with "blimps" which don't haul nearly as much. The Navy used them in WWII for anti-submarine patrol - imagine five guys in a camper going out for two weeks and staring at the ocean - but even that meager use went away with the invention of jets.
Eight football fields is a lot, but it's hardly impractical; runways at international airports require much greater areas than that. And the fuel costs for ferrying passengers on oceanic cruise liners is no doubt similarly colossal. Bearing in mind that I'm talking about a luxury trans-Atlantic airship, of the kind that people would pay hand over fist for. I've heard about the helium shortage (although I have yet to see it translated into a shortage of balloons at parties). I suppose we can rule hydrogen out as an alternative for obvious reasons. Are there any other lighter than air and comparatively inert gases that might function as a viable alternative?
Runways at international airports are multi-use. The Goodyear needs that much space just to sit. Nothing else can come close. And good luck taking off or landing in any kind of wind. Ocean liners can (A) haul a bunch of people (B) run on bunker oil. Blimps don't run on bunker oil, they run on avgas. As such, "luxury" is the only kind you'll get. And no, your choices are hydrogen, helium and hot air. Hot air is its own problem.