Just Me and My Mom is going.
I think the regular DDP is good if you are planning on a package/family style/character meals (and who knows when/if/how those will come back) a day. Also if you are going to the more expensive cs - BoG beakfast, Restaurantausaurus Burger and Sundaes, or Pizzafari family meal would be great deals.
The reserved seating packages on the DDP are good if you are already planning on watching the shows - we like the F! package at Mama Melrose.
One big drawback (for us anyway) is that it does not include apps. I like desserts but DH does not, wish we could choose one or the other. The alcohol - DD drinks, I am a Diet Coke addict although I would just give him my drink

I have also gone to Disney with a list of places I want to try and then end up going somewhere else (for convinience/hunger/lines etc), and it is so freaking hot in Sept you might not be too hungry - so keep that in mind too.
I had (for our cancelled trip last week

) been toying with the idea of a split stay and adding the DDP to the first half (4 days). The plan would have been Ohana dinner ($55), MM F! (43), Garden Grill (55), Tusker House RoL package (63). For cs - BoG for breakfast (29), FT BBQ, Morocco, and RB&S (29). The rest of the trip (4 days) I had booked the less expensive TS - Via Napoli, Sci-Fi, Plaza.
What others have mentioned is so true - everyone is different, check the menus of places you might like to try and see what the total would be. The DDP is (with tax but not tip) $78 a day, snacks are around $5-6 and you get 2, so around $68 for a cs and a ts.