Also, I wasn't properly reading the sidebar on the Influence power.
You can only use Dark Side points to generate negative emotions (and to do even this, you must spend destiny points and suffer strain). In other words, you can't choose to tap into the dark side and get them to be friendly with you.
Now, this is written more for the base form of the power, but I'm fairly sure it is/should be interpreted for the rest of the control upgrades. This causes it to only work about 1/3 of the time when using only 1 force die, and only a little more than half the time when using 2 dice (the max this system lets players arrive at).
I think the fact that most of the time, players don't want to take actions that either incur a fight or encourage anger in their foes will cause this to not get too broken.