Power
Power is a tricky question in stem cell research. On the one hand, you're actively developing the technology that might allow someone in 2067 to grow sixty more livers, because, heck, why not? And if that doesn't give you enough of a sense of power, remember you're working with cells that are about twenty-five µm in diameter (source). (That funny "u" with a tail is a micrometer, by the way.) If working with cells doesn't make you feel big and powerful, then we don't know what will.
On the other hand, there'll be times when you feel like a tiny little cell yourself. Next to the huge medical and pharmaceutical companies that want to develop the cell research you're doing, it'll be hard not to feel like the little guy who's getting his lunch money stolen.
And don't even start with state, federal, and international governments. No matter what country, stem cell research has to follow certain rules. And it can get messy. Take, for example, "informed consent." You learned about that in school. So you know what it is, right? But informed consent according to whom? The FDA? EMA? PMDA? They all approach the subject in slightly different ways. Just to make your life difficult.
Speaking of making your life difficult, federal governments can often control the purse strings too. The U.S. effectively shut down federal funding through the National Institutes of Health to any new embryonic stem cell researchers in the early 2000s (source). Developments like that can make things tough on your end.
Oops. Did you make a misstep, according to the government and industry giants that control your work? Then it's back to square one—or cell one, as it were.