I think it would be cool to make skyworld floating over venus. It would make sense, because the air density difference would allow skyworld to float. Then a weather system can also be implemented, which could include acid rain and meteor showers (Although meteors aren't really weather), since skyworld would hover partially above the atmosphere.

Sometimes redoing something small is fixing something big
I think there should be different zones that restrict you from being able to use the jetpack. It would not only reduce the power of the jetpack itself, but also give the vibe that Zone has a system of law. Part of the theme on Era is that it doesn't have law, or at least, the people don't obey it. I think Zone's theme should include a sense of order, hence the organized warfare, and my idea that a pvp arena should exist, rather than all out warfare on the streets.

The planets, on the other hand, shouldn't have law, because they're an entirely different story.