This is what I'd suggest. Suspend a large scrim across the street (you might be able to avoid cherry pickers if you can find suitable mounting points, eg telegraph (not electricity) poles (get permission) and steer clear of the lines, then use full colours lasers to project graphics, then for the finale laser fireworks which could be syncronised in Pangolin with firework booms delivered through a very powerful sound sysem. Jem's suggestion of flame cannons is also a geat idea.
If you can get the lights turned off, if its not that dim, preferably legally (we all know of the laser pen vs photocell trick) then obviously this will help.
There was a good example of some laser fireworks on a Youtube video but I can't find it at the moment.
Having said that, I'd also see about appealing the fireworks ruling and look for precedents in other events where it has been permitted. You really need to examine the reasons for the rejection and see how they can best be challenged. Maybe there's a lawyer in the neighbourhood who'd take up the cause for free for his neighbours?