I want MOAR experience. I need it, my deck sucks as it is.
of course, once we're able to build nice decks, there won't be a whole lot of room for additional "leveling up", so opportunities to improve our decks will probably come slowly.
EDIT: That is unless we can eventually get meta-game abilities like our opponents have. Forcing the opponent to not act for a turn and such. I suppose we could keep getting more powerful in that manner almost indefinitely.