Kesler would be up there for me. The guy only scored 23 points in 05/06, was mostly just a shutdown bottom 6 guy, didn't look to have a ton of skill outside of that to be a top 6 guy. Flyers signed him to a 1.9 million offer sheet. Canucks could have accepted that and got a 2nd from Philly in 07 for a guy who looked to simply be a shutdown centre. Pretty good return. But, instead they matched the offer and kept Kesler who would go on to score 40 goals, win a Selke, put up 70+ points twice, and be one of the leaders of the team in the playoffs of 2011. Glad they didn't give up on him
The Sedins are another good choice. They were 2nd and 3rd overall picks so it is a weird choice, but they were absolutely jumped on by fans and media before the lockout. I mean they only hit 40+ points once right before the lockout, and Henrik had two seasons with under 10 goals. They were called sisters, and soft, and a waste of two top picks in 1999. The team didn't give up, and they came out after the lockout as premier NHL players, winning 2 Art Ross's, a Hart, and a Lindsay.
I'd say those three, all around the same time too, were the most prominent in recent Canuck memory