Kevin,
I use the daily charts because it's good for an intermediate time frame lasting weeks to months. For a trading account, I'm comfortable with that time frame. If you switch to weekly, and you still want to risk about 2% of equity, you'll have to have smaller position sizes because your stop will be a lot farther away from your entry price.
So the weekly charts would be more appropriate if you want to stay with a position longer than the daily charts usually allow. And, in turn, you don't mind having smaller position sizes.