Deluxe DP for the above 2 adults x 14 days would give you a total of 84 TS credits
Day 1 - 4
Day 2 - 8 (signature)
Day 3 - 4
Day 4 - 4
Day 5 - 8 (signature)
Day 6 - 4
Day 7 - 4
Day 8 - 4
Day 9 - 4
Day 10 - 4
Day 11 - 8 (signature)
Day 12 - 4
Day 13 - 4
Day 14 - departure day maybe no TS meal
Total 64 Credits - so you could include 5 TS breakfasts or lunch, or add in other signature meals to use up all the credits.
I think with kids wanting to do character meals it is worth it. The regular dining plan might not get you enough credits to really make it worth it. the reason the deluxe makes sense is because for one adult you get 3 TS credits per day. On the regular dining plan you only get 1 TS and 1QS -- I don't think it will give you much to work with.
I attached the pdf for the participating locations -- when i noted signature there are also dinner shows that are 2 credits too - like hoop-dee-doo which i have never done but have heard great things about.
http://www.mousefantravel.com/sites/default/files/documents/2018DDP_Locations.pdf
nope the only thing is that QS meals can be broken down to i believe 3 snack credits.
It all really depends what your party wants to do. Yes QS is cheaper but you are not getting any experiences -- some restaurants alone are an experience. California grill (2 credits) is at the top of Contemporary -- from there if you plan your timing right you can watch the MK fire works from there. Ohana is amazing too (only 1 credit) but then you can go and watch the fireworks from the beach at the Poly. Discuss with your party - if you want character meals and want some better restaurants to experience and enjoy an adult beverage with your meal and you if you have foodies in your group i think the Deluxe is a no brainer. If your party is satisfied with QS meals and paying OOP for the character meals then you could go the QS route it just probably won't save you much money.
You really have to work the numbers from what restaurants you want and what it would cost OOP with only getting the QS plan for your other meals.