the best thing to do with the dining plan (assuming you will plan some TS meals) is to do a draft of your daily schedule and pencil in all the TS meals you WANT to eat if you were NOT on the DDP. Once you have that down, THEN compare DDP pricing vs OOP pricing. Only then can you see if it's a good deal for you or not. We originally booked our package WITHOUT the plan as I didn't want to be tied to ADR's, etc, either. However, we started looking at the dinners we wanted (3 are TS), and the breakfasts (3 are TS), and then assumed the rest are CS. Based on our math, we'll save approx. $190 using the DDP...so for us, it's worth it (we saved $235 last year).
Anyway, there isn't just one answer to this - it relies solely on your own dining desires and scheduling.
Good luck!