And just like Kingofrunes, I always also only do those episodes of the Saga as well when they are the ones that grant extra rewards. The other episodes are too time consuming to be worth it for me.
You know, you can just do ep10 or whatever your "easy episode" preference is everyday and open the boxes on the bonus day - makes for a nice 300k on weekends. Hmm... I should do that on my weak characters and collect 1m or so a week.
EDIT
On that note, thinking of how you get like 5 character cards on new accounts and they'd all be in basic difficulty... I could get 1.5m (before bank fees) a week to send to my main account by doing ep10 everyday.