Smile Engine Illustration

I was recently tabbed by PUSH in Orlando to do an editorial illustration. I've not done an editorial illustration in a hot minute, and wondered how well I would effectively address the concern of the client. The illustration was to have the headline of 'Generating Smiles to Power Success. Orlando is Good for Business.'
The illustration had to convey that Orlando's economy basically runs on smiles. Which makes sense, with Disney there, and all the other outdoor fun that can be had there. I know every time I've been there I've smiled. Usually it's been at some idiots that cut me off, but that happens in every city. I think it's cause I don't use blinkers and drive a good ten miles under the limit. I like to soak things in.
Anywho-the client liked the idea of an 'engine' of sorts that produced or ran on smiles. I was to provide some sketches first, and if they liked anything, they would commission the rest of the project. Here's my first round of sketches. I tried to keep em rough and 'sketchy', but wanted to give em a little bit more than just pencil doodles.

After seeing these, the client wanted a bit more to go off of before they picked one for the execution of the final. The client seemed to like the idea of the smile in the lighbulb, which I thought made sense. That being said, I pushed the sketches further, bringing them to about 50% done. Here those ones are.

The client liked the one on the far left, so I brought it into Illustrator and started vectoring my little ass off. The main comment to keep in mind was to make the 'engine/generator/ligh bulb thingie' futuristic, as opposed to the old-timey feel of the first two sketches.
Here's the final. The client liked it and I think it came out alright, but still want to add more little details and cool conveyor belts and smoke stacks on the engine.

(The negative space at the top of the illustration is to be where the TYPE will live. TYPE needs space. And I like to give TYPE enough space to live, so there ya go.