I hope you didn't take any offense to my "this is fun" comment. I totally understand the whirlwind of planning. Sometimes it is fun however for ME to step outside of my own planning and look at someone else's scenario. That's all I meant.
I agree that the room only discounts on both rooms wouldnt be the best way to go. As for the different free dining scenarios, you have to look at how much your party will likely eat. And you are completely correct that I didn't factor in the upcharge of having additional adults in the cost of the room.
Adding free dining and upgrading for both rooms= $468 for 20 adult TS, 12 kid TS, 32 QS, 64 snacks, and 8 mugs
Adding free dining and upgrading to one room with 4 adults= $336+ $120 (I think each add'l adult is $15/nt) so $446 for 16 adult TS, 16 QS, 32 snacks, 4 mugs, and $200ish room discount
Upgrading to DxDP in one room with 1 adult and 3 kids= $446.96+ $120 (add'l charge for adults in other room) so $566.96 for 48 TS or QS meals, 32 snacks, 4 mugs, and $200ish room discount
The second scenario probably makes the least sense. Between the first and the third, it would mostly come down to how much people will probably eat, how willing they will be to share, and if the additional meals, snacks, and mugs in the first scenario will all be utilized or if the $200ish room discount but lesser meals, snacks, and mugs in the third scenario would be a better option.