This would be one of those generic Next Generation episodes that proves that although the third season was basically the start of the series as fans know it, it's not the best of all possible seasons. It can sometimes be all but forgettable.
"The Vengeance Factor" is one of many, many episodes from the series where our crew is asked to mediate a conflict between warring factions. There were so many of these, it's surprising that none of the movies were really about it, but perhaps not surprising that its only nominal spin-off, Deep Space Nine based a part of its premise on the concept.
Unfortunately, there's not a lot to distinguish this one from the rest of them. There are even episodes from other series that are exactly like it but more memorable, "Battle Lines" from DS9 for instance, and that's just because it features the unexpected death of a recurring character.
Actually, if there's anything to talk about with this variation, it's that "Vengeance Factor" is one of Next Generation's periodic attempts to represent Riker as a Kirk kind of guy, who becomes involved with the female guest just because he's male and she's female. Of course, most of Riker's such relationships turn out miserable, even worse than Tucker's in Enterprise (and that's saying something!), and this one is no exception. But it's not even prominent enough to make too much of. It does tie into the resolution, but it leaves no real lasting impression, just another part of the unhappy ending.
That may be what you can best take away from the episode, its ambiguity. Star Trek can sometimes be stereotyped as fairly black-and-white. Heroes are pretty obviously heroes and villains are pretty obviously villains. DS9, again, was an exception to this rule, but Next Generation helped set that tone more than fans might sometimes admit. If nothing else, "Vengeance Factor" is one such experience to prove such an assertion.
So there you have it. You can probably skip this one, but it wouldn't hurt to have a look.
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Memory Alpha summary.