Altoona won't have the marquee value of the Indianapolis' prospects, nor will it have quite the numbers, but the Curve will have plenty of players worth watching. Quite a few can be described more easily as "interesting" than as out-and-out "prospects."
Catcher
Reese McGuire and Jin-De Jhang will both move up from Bradenton. It's a shame they can't combine their talents. McGuire continues to draw raves for all aspects of his defensive play, but the Pirates are still waiting for him to hit the ball with any authority. Jhang hit very well last year -- he's very hard to strike out -- but the Pirates don't seem to be sold on his defense, although he throws well. Jhang will probably get a lot of time at DH as well as behind the plate.
Corner Infield
With Josh Bell and Jason Rogers in AAA, Jose Osuna will get pushed back to AA despite a solid 2015 season and a big season in winter ball. Osuna will return to his normal position of first base, where he's a good defender, but he needs to be more than just a solid hitter to move forward at the position. Edwin Espinal and Stetson Allie will also be with Altoona. The Pirates have always liked Espinal's bat, but he's never put together more than a mediocre season and he wasn't in the best shape in camp. Allie will be in his last year before minor league free agency and will probably see time in the outfield, especially with Austin Meadows hurt early in the season.
The third baseman initially will be Eric Wood, with Espinal also possibly seeing time at the position. Wood has power potential, but like Espinal he hasn't managed to tap into it much in games. He's returning to AA after struggling badly there last year. Eventually Wyatt Mathisen should join the Curve, but he's out for now with shoulder soreness. He's yet another hitter who has yet to tap into his potential, especially in the power area.
Middle Infield
The Altoona keystone combo will be fairy straightforward initially, but the big question eventually will be whether Kevin Newman and Kevin Kramer can earn promotions during the season from Bradenton. Unless and until that happens, Altoona will have Erich Weiss at second, and some combination of Chris Diaz and Anderson Feliz at short. Weiss is yet another hitter who's shown some ability but needs to hit with more authority. Diaz has shown a good glove but hasn't hit much. Feliz is also a good defensive player. He spent six years in the Yankees' system and showed some hitting potential at times, but he didn't play all that much due to a combination of injuries and getting slotted as an organizational player.
Outfield
For the third straight year, Austin Meadows, Harold Ramirez and Barrett Barnes were slated to comprise the outfield for one of the Pirates' affiliates, and for the third straight year injuries have derailed the plan. This year, at least, there may be a relatively limited delay, although there's no timetable yet for Meadows' return from an orbital bone fracture he suffered in March. Assuming he returns before too long and continues hitting -- something he's done everywhere he's gone, including Altoona late last year -- he'll be raising some interesting questions, with the Pirates having locked up their entire outfield. Ramirez was impressive at the plate in the spring, but needs to impress the Pirates in other phases of the game. Barnes, apart from staying healthy, needs to start tapping into his power potential more consistently.
The Curve will have an interesting backup outfielder in Justin Maffei. He's benefited repeatedly from Meadows', Barnes' and Ramirez' injury troubles, and has taken advantage of his chances; he's had an OBP of .376 in the equivalent of roughly one season in high A. Allie and organizational guy Jonathan Schwind will probably also see time in the outfield.
Rotation
The Curve will open the season with a rotation of Tyler Eppler, Clay Holmes, Cody Dickson, Jason Creasy and David Whitehead. The Pirates seem to be very high on Eppler. They skipped him over low A last year even though he missed the first half of the season, then promoted him to AA near season's end after just 61 innings at high A. He throws in the mid-90s but doesn't miss bats. Holmes missed all of 2014 and most of 2015 due to Tommy John surgery. He pitched even less at high A than Eppler, but the Pirates are moving him up to AA just the same. Dickson bears a lot of similarities to former prospect Zack Dodson; he has good stuff for a lefty, but so far hasn't shown consistent command. Whitehead, who was the return for Charlie Morton, and Creasy are both very hittable and have the look of upper-level organizational pitchers.
Bullpen
The Altoona bullpen will consist mainly of pitchers returning from last year, with two surprising additions. Those would be Dovydas Neverauskas and lefty Jared Lakind. Neverauskas has always struggled with inconsistent velocity and command, but a move to the bullpen seemed to help last year. His K rate actually plummeted, but he started getting hitters out anyway. He threw fewer than 17 innings in high A, but will move up to Altoona. Lakind, a converted first baseman, has never pitched above low A and hasn't gotten a lot of innings due to some injury issues. More importantly, the Curve will have the pitcher with the best name in the farm system in Montana DuRapau. He's a darkhorse who shot up through three levels last year on the strength of decent stuff, highlighted by a good cutter, and excellent command.
Other returnees from 2016 will be John Kuchno, Jhondaniel Medina, Brett McKinney and lefty Josh Smith. Kuchno is an extreme groundball pitcher who misses remarkably few bats. Medina had some high K rates in the low minors, but he walked nearly as many as he struck out in AA last year, as his stuff didn't seem to hold up well at the level. McKinney has good stuff and gets a decent number of swings and misses. He spent half of last year at AA and took one for the team a couple times, leading to a 7.50 ERA. Smith had a rough year with the Curve last year, walking more than he struck out. Altoona also will probably get Carlos Perez back late in the year, but he'll miss 80 games due to a PED suspension.
Lineup
C: Reese McGuire
1B: Jose Osuna
2B: Erich Weiss
3B: Eric Wood
SS: Chris Diaz, Anderson Feliz
OF: Austin Meadows (eventually), Harold Ramirez, Barrett Barnes, Stetson Allie/Justin Mafei
DH/C: Jin-De Jhang
Rotation
Tyler Eppler, Clay Holmes, Cody Dickson, Jason Creasy, David Whitehead
Key Relievers
Montana DuRapau, John Kuchno
Top Prospects: Meadows, McGuire, Ramirez
Breakout Candidates: Eppler, Holmes
The Curve should have a good offense, despite not having great power, and a very strong defense. The rotation may not be especially good unless two or three out of Eppler, Holmes and Dickson break out. The bullpen may be a problem beyond DuRapau.