The guests will be smiling after the ride. It's the ideal time to sell them some trinkets. We get another boost from building a stall over the track. The entire increase came from the first stall.
We build a mirror image coaster with the stations aligned. Even without synchronizing, exitement increases due to track proximity.
We synchronize both coasters - each receives a 0.40 excitement boost.
We add theming. Fountains seem to help. Each scenery object within five tiles of the entrance provides a boost, up to about forty objects. Full disclosure: the excitement was stuck on 6.99 until I clipped the track and lowered one land tile. Reducing from four to three underground track pieces provided the last 0.01 boost to get to 7.00 excitement.
So there you have it. A modest little coaster with only two drops(!) gets turned into a scenario beater. The flatland price to build the coaster is only $6,187. The coaster is available in Track Pack One - Racers.