Short tasks and play as much as you can.
On week days I get up half an hour early each morning to throw all my characters on 4 hour quests (3 hours or less if they don't have a 4 hour, or 6 hours for jasmine). At lunch, I collect, and put belle, gaston, lefou, kai, rapunzel, mother gothel, shorty, hans, and anna on their 10 min quests first, THEN, featherduster, maximus, gerda, conli, the bishop, and oaken on 30 min quests. Third, put all remaining characters on 4-6 hour quests. If you have a 60 min lunch like me, you should still have time to eat and put your 10 min characters on one more round of collection, then take all your 30 min characters and put them on 4-6 hour quests. When then 10 min folks finish, put them on 4-6 hour tasks as well. When I get home from work, I collect again, and then depending on what I need to do, I either a) put every character on their shortest quest and collect continuously or b) evaluate how much time making dinner/errands will take and put my characters on 1-3 hour tasks. Before bed, I try to get in an hour of nonstop play with everyone on their shortest tasks to generate what I can. Just before I turn off the game, I put everyone on their longest task to run over night. Doing this daily, I average 6-12000 a day. On my days off, I play as much as possible with short tasks and can average 12-18000 a day.
Depending on where you are in the story, many decorated buildings will boost your totals (set rotunda on normal for active playing and xmas decor when letting it sit overnight or away from game 6 hours). The market stalls do help, but only if you have enough pc to purchase them without taking away from your story.
Because I didn't know what I was doing, I spent pinecones on things I didn't need, and now I learn I still need three trees and urns and who knows what else. I might have been able to catch up if I knew all this a week ago when my vacation started, but I go back to work tomorrow and won't have anywhere close to enough time to play now. Boo.
