In an Insider only piece at ESPN, Corey Pronman listed his top 100 NHL prospects, and three Rangers made the list. The top prospect is Jonathan Drouin from Tampa Bay, and the rest of the prospects are behind the pay wall. Chris Kreider (41), Danny Kristo (54) and Pavel Buchnevich (69) made the list. Pronman also noted the organizational ranks in a separate Insider piece, with Colorado being the top team. The Rangers were ranked lower, but this is mostly because most of their prospects are in the NHL already.
Both pieces are worth the read if you have access.