Getting all commie with the labour day parades, are we there, comrade Ratshot?
Nice idea though :] The only actual gripe I have with this one is that there's no hint of those construction works you've mentioned - but it does work perfectly as a parade! I like Bart's idea regarding that "bumpy road to collaboration & success" (you like the name, admit it :D) - perhaps you really should try using plates to change the height of the road here and there.
I also agree that, apart from the minifigs, this MOC isn't really full of details. But then again, it's the minifigs that really count (literally!) in any parade, so I guess this is fine. Seeing as you're short of bricks, I'd suggest adding some more subplots such as the one with the rat in order to liven this up even more :]
Oh, and how about some cheerleaders with batons and everything? It's a parade after all