I'll throw Dan Cleary in here as well. I remember the hype that he had as a 15-year-old, which continued all the way through his draft year. He started dropping in the rankings during the season, ended up going....I think it was 13th or so to Chicago.
He's another guy who's had a serviceable career but nothing close to what anyone would have predicted. I think his was a unique case because the hype had been there for a lot longer than just the preceding year, so some of the fall was attributed to the idea of familiarity breeding contempt and his game being overanalyzed.
I'd also wonder what to make of the IHLers of the mid-1990s (Radek Bonk, Sergei Samsonov, Robert Dome, and Patrik Stefan). I think each one of them went far higher than their skill set would actually dictate had they been in the OHL or overseas, possibly because the level of competition created an idea that they were more of a sure thing. All were first-rounders, but Samsonov sort of mirrored Clearly in the hype and subsequent minor fall. Dome and Stefan just never panned out.
I did think of another while editing. Evgeny Lazarev was a huge wild card who had a lot of hype, but the subsequent issues with being allowed to play (ending up in court) and his own poor training habits led to him being tagged as a sort of Hossa/Riesen/Cerada unknown. Obviously he did nothing in the NHL.
I'd be interested to see if we could conjure up some names of guys who weren't anywhere on the radar the year before they were drafted who suddenly shot up to the first round and how they developed. I remember David Legwand being one of those guys, but I don't want to continue on this path...I'll save it for another thread.