All objects that are anything more than a static lump (foliage, rocks, etc.) should have control options. Cannons, as you mention. Lights, set pieces (pirate band as an example). For animatronics, we should be able to turn off animation, control the frequency that it animates, triggering conditions, etc. For lights, the brightness, hue, throw, edge (sharp, fuzzy, fade-out), maybe even shape of lighted area (round, square). For the eventual, inevitable placeable park speakers: the sound file - including PC-provided sounds, the volume, other speakers in the group, trigger (for sound effects), frequency, duration (how often, how long) and with park announcements - "try this new ride; child found; missing, etc."
And a park effects control panel so we don't have to walk the entire park to make changes to these controls. But that would require a park map generator, I would imagine... My want list seems to be growing exponentially - apologies .
Robert