The noise complaints issue has always been ridiculous to me. Considering the active studio & theme park existed long before the surrounding neighborhood, they shouldn't have to cater to these demands as much as they do. If you choose to live next to a working movie studio/backlot and/or a theme park... you would think that accepting the "noise" would come with it.
I think that any nighttime show with loud music, soundeffects and pyro should be able to go up until midnight. I can't remember if it was 10pm or 11pm, but that was when IOA would have to close The Hulk & Dragons for "noise" at night, even if the park was open later. So any nighttime show at USH should be able to happen at 11pm at the latest depending on park close.
As for IOA not having a nighttime lagoon show, there has been rumors for a long time that one was in the works. We'll see if that ever happens though.