Technical, but very important consideration - dismantling. The party is over, the golden carriage has to turn back into a pumpkin and taken out of the room quickly and with minimum inconvenience. What other creation can come close to balloon sculptures?! 

In this case disassembling is not the job, it is FUN! In huge gatherings (MCI arena, now Verizon center) and in small ones (like a birthday party) the best gift you can make to the guests is plastic fork and permission to pop the balloons on the structure.  That would be the culmination of the party! People remember it for years - take my word for it!  If you think it will work only for kids?  WRONG ANSWER!   I see it time after time. Adults absolutely love it. Now, guess, how long does it take to clean the room from balloons sculptures when you have so many eager helpers? Right: count to three! Done!

Once we dressed up a stadium in DC for a party for season ticket holders. Big crowd, a lot of kids. Our team of decorators worked a little more than 24 hours. When the party was over, the public (and the kids) were informed that they are welcome to take balloons down and take them home. They figured, they would rather pop them right now! It sounded like a war! In 5 minutes there were not a single balloon there. What else can be dismantled that quickly and with that much fun?