No, the stadium missions are just money makers and ways to pass the night. You didn't list the RC toy missions, or the dirt racetrack missions, or the racing missions you get in the car dealership, but then none of those give a bonus. But neither does Cherry Popper. All CP does is get you the asset.
Ambulance gives you 200 health(or is it run forever?), and I think there are 11 or 12 levels. Fire makes you fireproof(tho not explosion proof) and there are a similar number. Vigilante...I forget. Armor to 200, probably. I guess Pizza does whichever ambulance doesn't. You have to get 100 total fares for taxi, but not at once, thank god. So I'd log about 10-20, get tired of it, and go kill people for a while. The jumping taxis RULE, for a while I didn't drive anything else(and with the Zebra Cab, you've got decent speed and handling.) Nothing is more satisfying than getting a wanted level, having a cop chase you and one coming head-on, and jumping the oncoming one to hear the cops smash into each other.
Man, I miss that game.