Actually liquid H2 has energy density of 39 kWh/kg, where common CH fuels are around 12-13 kWh/kg. So about 3x more energy per kg then conventional fuels.
Note that H₂ boils around 20-30K (depending on pressure). Once you take into account the weight of the insulated tanks, liquid H₂ is going to have much worse energy density.
Liquid storage I believe typically gets up to about 20wt%, so you're talking around 7.8kWh/kg. Compressed storage is around 6–10wt%, so up to 3.9kWh/kg.
Yes, but that's without the container, which is very heavy for the hydrogen, while a plastic bag is already good enough for fossil fuels.
That's without the weight of the storage and potentially fuel cell surely.