Losing your MVP will shake your confidence.
I don't disagree, but if you're that mentally fragile then you didn't deserve to win in the first place.
Vancouver was just the most impressive the way they rolled three lines, had a great mobile blueline, outstanding goaltending, and just destroyed the Stars and Leafs after they got hot against Calgary. They battled a superior and battle hardened Rangers core and it could have gone either way. Their opponents were better than the Lightning or the Hurricanes.
Calgary was the second best, they had a pretty solid core that they rode for the better part of a decade after 2004 as a decent contender every year.
If by "core" you mean two players, then yes. Iginla and Kiprusoff carried the Flames in 2004 and after the lockout. This is why I rank Calgary third out of the three. 15 grinders working their butts off, one all-star forward, and a hot goalie. Hey, it worked, no shame at all in that. But they could only beat you one way, using one style. Edmonton and Vancouver were deeper and more versatile.
Edmonton ripped off a 7-game winning streak in the midst of their run. Similar to Vancouver cruising past Dallas and Toronto. They were the only team of the three that did not face elimination at any point on their way to the final. Calgary only faced elimination in Game 7 of round 1. The Canucks (oddly, since they seem to be the consensus best team in here) were almost toast in round 1, needing to win three straight in OT to comeback on the Flames.
It should be pointed out that Calgary was the one team that actually looked as though they were going to win the Cup at one point. The Canucks and Oilers both had to dig out of 3-1 holes to force a 7th game. Calgary never trailed in their series.
Edmonton was the worst, just a Cinderella team with no business being there. Losing Pronger hurt, but their total lack of success after 2006 and their inability to beat Carolina really says a lot about how they really just fluked it. Carolina was pretty hot that year but they're probably the one of the least talented cup winners of all time.
Carolina might have had the most heart out of all the Cup-winners I've witnessed. That team gets crapped on and called a fluke constantly in these parts, but I'd stack them up against any of the other post-2004 winners. They only maintained it for one year, but for that one year, they were the best team in the game. Vancouver or Calgary wouldn't have likely beaten them either.
Edmonton's lack of success after 2006 is irrelevent. The team was gutted in the off-season. Pronger, Peca, Spacek, and Samsonov were all lost for nothing. You don't think that the Canucks would have gone in the crapper in 1995 if say Linden, Ronning, Courtnall, and Lumme all walked away in the summer? What if Iginla was traded for Joffrey Lupul after 2004?