Yeah I'm taking the flying fortress or Nero's dome. This was over the moment you gave a flying fortress with lasers,

Aestus Domus Aurea is a good Noble Phantasm, but the Hanging Gardens just have SO MANY useful powers. It counts as being in the Middle East for Semiramis so she gets a Fame boost, it boosts her parameters, her attack power, and it basically sets enemy fame to 0, it can summon hundreds of Dragon Tooth Warriors, fire barrages of small lasers and huge Wave Motion Blasts, can move itself around pretty fast, and unlocks Sikera Usum.

Nero would also almost certainly be unable to activate Aestus Domus Aurea if she was inside the Gardens, since Aestus is only a B rank Anti-Team NP, while the Hanging Gardens are an EX Rank Anti-World.