As far as I'm aware, hydrogen is actually the more dangerous; since helium doesn't combust.
When dealing with lift of this nature, you need to think in terms of density. Compressing a 'lighter than air' gas makes it more dense, and actually causes it to produce less lift. So assuming you have a container and fill it with helium or hydrogen, it's going to float a bit. If you keep filling it (and it retains the same volume/shape), it will float less and less, and eventually not float at all.
Submarines work in a similar manner. By making their volume more dense (usually letting in water to the tanks) they can sink under the water at a controlled rate. Pushing water out of those tanks reduces the density and lets the submarine start floating upward.
The newer 'airships' in those videos work just like a submarine, but take in and release air to rise and descend.
I think it'd be possible for high altitude airships, but they would take some effort. Realistically you'd need to keep your crew warm and have adequate oxygen and pressure, which means it would likely have to be closed in. The airships in the game currently are 'low' altitude airships.
But for gameplay.... I can't see much enjoyment flying high above the clouds free of obstacles and other ships.