As for the times I like to eat, its not about efficiency for me. I try to keep to the same schedule I do at home which is 8am Breakfast, between 12pm-1pm Lunch and 6pm Dinner. That noted, I think these times are "efficient" because they never seem to interfere with any parades or fireworks viewing.
For me, its all about getting value from the plan. And if you follow these
DDP "rules" you will maximize your DDP value.
1. Always use DDP Adult TS credits on DINNER!!!
If you want to book a Character BF or 2, pay OOP because an adult CBF is 18.99 for most of them (much less than the cost of an average dinner). Note: If you want to use your Adult TS for Character BF's, you likely will not come out ahead on that day (but it should still be pretty close to breaking even - within $5 of the daily plan cost).
2. Addendum to #1: If you have kids with you at the Character BF use their Child TS credits for these meals while you PAY OOP. This is because a child CBF is usually 10.99 (while child TS dinner is usually $7.49). Of course you will have to pay OOP for 2 of their $7.49 TS dinners during the stay if you do this.
3. Never (repeat Never) use 2TS for any meal even CRT though its tempting. Think of it this way: CRT or Le Celier
and Tutto Italia! p.s. I'm not saying don't eat in the Castle, just if you do you're losing value. You're better off paying OOP.
4. Always use CS credits on LUNCH.
Same principle as #1, but this time since lunch costs more on average than breakfast.
5. Use snack credits on BF items, not snacks. Most items under $4 qualify for a SC. You can get a nice coffee roll or mickey muffin at MS Bakery, Boardwalk Bakery or Starring Rolls each morning for a snack credit. Use another credit to split an OJ, pay OOP for a coffee and you'll be set. It won't cover all your BF's so the days you aren't using SC for BF items pay OOP or go to a character BF and have some fun following rules #1 and #2.
Those are the basics I have followed to get the most "value" from the DDP. My last trip I followed them to a T and figured I saved about $230+ for a family of 2 adults and 1 child for a one week trip.
DISclaimer: All "rules" have exceptions. Look over the menus, see if a restaurant appeals to your tastes, look at the prices of items you would order and go from there. Don't let the DDP dictate how you eat (or this post for that matter)

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I'm going in May for some "boys only" time with my DS4 and booked these ADR's on Sunday

:
16: Tony's Town Square Dinner (TS for me, OOP for DS4)
17: 1900 Park Fare Dinner
18: Whispering Canyon Dinner
19: Crystal Palace Dinner
20: Ohana BF (OOP for me, DDP for DS4), Tutto Italia Dinner
21: Fantasmic Dinner Package at Mama Melroses
22: Sci-Fi Dine-In Lunch (TS for me, OOP for DS4). Yes I'm breaking my own rule here by using an adult TS for lunch, but like I said, don't let the DDP dictate how you eat. Star Wars Weekend today

and EMH in Epcot that night so we'll do Sunshine Seasons CS that night (one of the best CS at WDW IMO).
23: 1900 Park Fare BF (OOP for me, DDP for DS4) then afternoon Magical Express home
