Sure, I think you have to start with what motivates people. Bottom line is money and fun. People want to play with fun decks and make money. I would propose an alternate prizing scheme geared to increase both.

First, I would half the prize money for winning certain events where they want to push casual play. PCQs seem like a good place to start. Then, I would generate a list of cards that would earn you HALF the prize money if you happen to win with that card in your deck. You finished first? Oh, but you played with Enemy of my Enemy, and that means your prize money is HALVED. However, if you finish in the money, and you don't have any of the listed cards in your deck, then your prize money is DOUBLED. There could also be allowances made if you're using Dr. Light, in say, a mono EE build or whatever.

Obviously, they would have to tinker with the prizing payouts, and depending on the payout, it's possible for the person in 2nd to make more money than 1st if they did it with an original deck not based on cards seen all over the top 8 at a PC.

Secondly, make bounties during the course of the tournament. After the first round or two depending on the size of the tournament, a judge could go through the decklists, and declare, if anybody beats a deck with this team in it, they get a prize. If you beat it with an Arkham deck, double it. It doesn't matter if it's just a pack of cards. It's FUN. I have to thank our own Erick for that idea. He's cool.

In fact, I suggest a BCS type ranking system headed up by US the players, that vote on which teams are the best, just like college football, in order to facilitate these subjective decisions. That means, each team is assigned a certain number of points based on voting, and then they are ranked. These ranks could be updated monthly, or after a major event whichever is most popular.

Based on this "BCS" type system, judges at these casual events can better determine the worthiness, or value of a bounty, if the number 20 seed (Arkham?) takes down the top seed (Titans?). Now, all of this is very subjective and would take a lot of work (I know team ups mess with this, but I'm sure a weighted system can be worked out), but sometimes that's what it takes.

I know Magic and other games are less complicated, but one of the key differences if I remember correctly, are that there are what 5 or 6 different colors in Magic? You can play a blue, a black or a red deck or whatever. There are something like 30+ teams in VS, so it's harder to make everybody a winner, and I understand that. Given that, making events that reward creativity will boost casual play in my opinion.