Weekly tournaments would start to take a toll as people start to get burnt out from too many. From my experience, having tournaments too often works in the beginning, but eventually results in very low turnouts and often not having as much competition in them. Not to mention that $10-15 a week would make it hard financially for people.
I support regular tournaments, just not every week.
As for the pm tier list, if you read the comments below it they talk about how pm is much more balanced than other games and so the tier placement isn't as big of a deal. Also, tiers don't always refer only to how good the character is. Ease of use is also taken into account and expressed in the form of tourney results. Squirtle may be freaking good if you can master all his technical tricks and mind games, but why put that much effort into him when you can get good with fox with a much more straight forward play-style a lot faster. In that sense, tier lists are in no way a means to discourage you from using a certain character. Unless the character is truly garbage, if you put the effort into mastering that character you can go far. Especially in a game like pm where they focus on trying to balance so the low tiers aren'tas far from the top as in other games.