In many sports, there are positions and roles that you don't really notice unless something goes wrong. Football centers, baseball catchers, the baton pass in track relays. To further add insult, it takes a ton of familiarity to recognize the differences between mediocre and good.
In my novice volleyball fandom, the setter is one of those roles, but the good news is UB has a pair of experienced setters returning to the team in 2015 to help turn successful defense into high-quality offense.
Last year, then-junior Marissa Prinzbach and then-sophomore Megan Lin traded off the setter role for much of the season. Prinzbach had transferred to Buffalo following two years at UConn, while Lin barely saw the floor behind Dani Reinert and Taylor Pritchett in her freshman year at UB.
The beginning of the season saw Lin starting, but though she would play in every match on the season, she wa supplanted as the primary setter by the beginning of September. Prinzbach was injured for a stretch in early October, but returned to the bulk of the duty. Late in the year Coach Reed Sunahara used both Lin and Prinzbach shifting from a 5-1 offense to a 6-2 setup.
Quickly, the difference between the two is in the number of setters (1 or 2) and other players (5 or 6) in the rotation. You can learn more in this post from commenter Paige Miller that explained it well last year.
In the specified duties of the setter, it would be hard to argue Prinzbach wasn't the superior of the two last year, though it's not as large a gap as you'd think on a quick reading of the stats. Prinzbach's three-inch (5'11" - 5'8") advantage on Lin made her less of a liability when on the front line, but Lin was the team's best server, finishing with 28 aces.
On the year, Prinzbach more than doubled Lin's assists per set, but that number is brought down by Lin's appearances as a defensive and serving specialist in matches where Prinzbach was the primary setter. The best I can do is look at their relative success as the primary option. When Lin totaled fewer than 10 assists, Prinzbach was never below 30 when getting most of time, but Lin had a few matches with fewer than 30 among the eight that Prinzbach missed entirely. Their numbers were roughly even in the last half-dozen or so matches when UB was using the 6-2 rotation.
I unfortunately am not really able to talk about further specifics of setter play. Anecdotally, I felt when I watched last year that Prinzbach had a little better rapport with her hitters and accuracy when delivering sets behind her, but it's hard to quantify something the increase in attack quality that results from something like that. Hopefully Paige and his expertise will offer more in the comments below.
It's also worth noting that in 2015 there are not only these two but a further pair of freshman setters. I've mentioned the roster imbalance before and while I think it unlikely that a freshman leaps two setters with experience, we don't have anything to go on with Blair Brown Lipsitz yet. Furthermore, the one 2016 recruit I know about right now is also a setter.