I got on a caffeine test group at work long ago. I fonud the project interesting, so I started attending their meetings. Tea, I learned, has a "dampening" effect on caffeine metabolism (and it has less than coffee to start). Their idea was to develop a soft drink with the same impact, rather than a caffeine rush and then nothing, a drawn out impact over time.
I started following another project to develop artificial sweeteners so sweet you'd only need a tiny amount making the safety concerns less. They had some good candidates, but they all had a lingering aftertaste. Those folks would make compounds in the lab and then taste them. Oof.
The other interesting thing is how many molecules taste sweet and look nothing like the others that taste about the same. Saccharine structurally is very different from sucrose.