Here's a look at how various Steelers figure in a set of rankings by ESPN.
Quarterback: Ben Roethlisberger. No. 62 overall, No. 10-ranked quarterback. This looks about right. Roethlisberger has a very good corps of receivers this year, led by Mike Wallace, and he (Roethlisberger) actually figures to play the whole season, unlike last year.
Running back: Rashard Mendenhall. No. 15 overall, No 8-ranked running back. You might make a case that Mendenhall should be ranked higher, given his prominence in the Steelers' offense. Look out for Isaac Redman in the late rounds.
Wide receiver: Mike Wallace. No. 21 overall, No. 6-ranked wide receiver. Wallace has his sights set high this year, and hey, why not? It's his third year in the league.
Hines Ward, No. 115 overall, No. 44-ranked wide receiver. If you're picking Ward to be anything more than a bench player, you must be in a really deep league. He's had great fantasy seasons before, obviously, but he was unimpressive last season, and this season, Antonio Brown and Emmanuel Sanders will cut into his opportunities. Look for those guys in the late rounds, especially Brown.
Heath Miller, unranked among tight ends. Miller is only really an option if you're in a deep league.
Steelers defense: No. 139 overall, No. 1 among defenses. As ever, you should be waiting until the very end of the draft to pick a defense. The Steelers will rack up sacks, but their secondary could prove frustrating.