What Sundin would do for Vancouver is get them into the playoffs and give them a chance to go deep, which makes the team more money and gives the fans something to be excited about. It's not like signing him is going to kill the team for the future because it won't at all.
I also don't agree that they have no shot. Are they one of the top 10 teams in the league? No they aren't, but if you get one of the top 10 players (and Sundin is a top 10 player) to go along with some good young guys in the Sedins, a good defense and the top goaltender in hockey and you have a shot. They just need to get into the playoffs, and then you have the chance of Luongo dominating and winning you games you have no business being in.
I also don't agree that they have no shot. Are they one of the top 10 teams in the league? No they aren't, but if you get one of the top 10 players (and Sundin is a top 10 player) to go along with some good young guys in the Sedins, a good defense and the top goaltender in hockey and you have a shot. They just need to get into the playoffs, and then you have the chance of Luongo dominating and winning you games you have no business being in.