We need to stop calling Edstrom a center until they actually play him at center. He played exclusively wing on a line centered by Roobroeck during the rookie games against Philadelphia — other wingers like Chmelar, and Sykora were taking draws over Edstrom on the PK. He played wing all of last season. He's a wing.
Fortescue isn't a puck driver, he's a defense-first player with decent puck-moving abilities. The Rangers don't have any prospects matching your description. They have strong skating defensive players in Fortescue, Mancini, and Emery.
The issue with the Nash deal was when it was executed. They needed to make that trade at the 2012 deadline, not during the offseason. The main difference was the inclusion of Del Zotto while the Rangers would've kept Dubinsky. Losing both Anisimov and Dubinsky cut their depth in a way that necessitated trading Gaborik for replacements. There's a chance they do a bit better if they still had Dubinsky and cut Del Zotto loose sooner. You would also have Nash before Torts and Gaborik's situation went completely sour.
Dan Boyle. The Rangers let go of Stralman, one of their best defensemen, so Sather could finally get one of his white whales. Boyle was cooked by the time he got here and forced the Rangers to use assets to get a replacement PPQB in Yandle. Boyle was a bad addition to a cup contender.
Dawn Braid had been doing monthly skating sessions with Hartford this past season. If Drury/Martin could get her to work with Hartford, she'd probably making some kind of cameo during Rangers training camp. I'm sure Rempe also has someone he works with locally in Calgary.