Spoiler - so far I have found the following combos
Monkey King - Horns and clown smile level 2
Santa - Stun level 2 and glasses level 1
Pirate Life Level 2 and Eyepatch level 1
Luke Skywalker - Graduate level 2 and sunglasses level 2
Rorschach - Hat Level 2 and mask level 2
I made it through the whole game doing pet shop first on the 2 spot from the right w/ news then boutique at right. From then on add a building when you can or upgrade if you can't, adding News at each stop and a busstop around Day 11 (wait until the day is over...free busload) My ending order from Left to right was Market , Rest., Elect., Furn., Jewel., Toy, Pet, Bout.
4.0 sec. #1. Woohoo! But there is no incentive to play on the harder levels as there is no bonus for doing so. If your time was multiplied by a percentage based on difficulty I might try level 5 or impossible.
OK I've watched the video, but there is one thing I must not be doing right. They seem to jump quickly and vertically out of a tailslide for huge height. Is there some angle you need to hit it at to do that?