For 2 adults and a 3 year old and a 2 year old....
I am trying to decide on OOP, DDP, DDDP
Generally speaking having a child in the mix makes the DP a much better value. Keep in mind your 2yo can share for free and she can eat off her own plate for free at buffets. For your family the nightly cost for the basic DP is: $86
If you had 2A & 2C CSmeals a day you'd probably spend $60-70 each day including just drinks and entrees for two adults, no desserts. Snack items or adult desserts would be additional.
The question comes in how do you want to eat on vacation? Do you mind paying each time? Do you want the convenience of the plan and having meals pre paid? Do you want to take your children to TS character meals? Disney can be done on lots of budgets, just have to decide which you prefer.
We were a family of 2 adults and a 5yo. We were on the DP and loved it. I can't see doing Disney on site w/o it, but that's just my preference. We ate a TS meal each day (Narcoossee's (2TS), Coral Reef lunch, Chef Mickey's late bfast, Boma, Hollywood & Vine dinner). We only had 5TS credits so we paid OOP for the little one at Narcoossee's(his meal was under $10) and for the adults at Chef Mickey's.
We shared a lot of counter service meals. Often if you order the combo meals or platters you get a lot of food. Generally speaking we ate CS this way: my nephew and I usually split a combo meal or he got his PB&J kids meal

. My mother got her own meal, but anything on the table was fair game to be shared.
If you decide to do a TS meal daily the DP is probably your best bet. Here is a possible "cheap" character meal day:
Breakfast at Chef Mickey's or Hollywood and Vine: $63 OOP with tax included
CS meal and snack shared by the 2/3yo: $4-7
CS Dinner for the family: $30 including tax
No snacks included on this day
You can round your OOP cost to $100, more than the DP and you still didn't get 2 of the snacks you'd get on the DP. You also paid taxes that are included in the $86 fee for the DP
Honestly, the Deluxe plan is probably more food and restaurant time than your little ones need. With that plan you probably want to have 2TS meals per day and that may be asking a lot of any 2 and 3yo and the parents who have to keep them "happy". There is so much to do at the parks and resorts I'd give them enough time to do those things rather than sitting it in restaurants or even worse, restaurant lobbies.
Sorry for such a long post, but I could almost see the wheels churning for you in your post and just wanted to share our experience and churn some numbers for you!