I like the deck thing: it will force all the players to make and learn to play with at least 2 different ELO decks, making the game more challenging. Maybe some people will even discover a deck that suits them better then the Rescue or Uppers deck they just looted of the strategy forums. If you're a serious elo player, you'll have more then one deck so it shouldn't pose any problem
I think its great that you will temporaraly ban a clan. it might be cool to randomly select one as t4rry said. you know what else might be fun? randomly select a few clans (4 or 5) each week and they are the only clans you can use for elo that way clans that don't get as much action may be used (like Nightmare, junks, Sentinel, and Bangers)
12 Daily Tourneys per day + Play = you can open a Pack of cards "without" having the need to buy credits within just 2-3 days..(or 2-3 packs per week) = more cards for everyone.. = public market card prices "might" go down because of increased supply of cards or when a clan is banned for a week..
for ELO..I'll go with Jade and Cauliflower's comments and suggestions..
What I ment by "banning players" is that it should be ensured, that a player cannot win cards (collectors mainly) two following weeks. I don't know weather this would be a problem in this system, were there are more cards, and more possible winners, but it deffinitely adds to the fairplay to the game.