Since you are staying off site you wanted to avoid the parks that have extra magic hours which according to the Official Disney Site are:
Dec 10 AK am
Dec 11 MGM pm
Dec 12 Epcot am
Dec 13 MGM am AK pm
Dec 14 MK pm
Dec 15 Epcot pm
Dec 16 MK am
Dec 17 AK am
I would assume you don't want to go to a park on your arrival day or departure day 10th and 17th. I always separate two park days with a rest/water park/DtD disney. So I would take 13th as a slow day for sure.
Also MK has the
MVMCP on Dec 11, 13, 15, and 16th so you want avoid MK on those days because they don't show the fireworks or the spectromagic parade unless you have tickets to MVMCP of course. So that leaves you with going to MK on the 10th or 12th. Assuming the 10th is your arrival day...I suggest going on the 12th.
I noticed that there is a Fantasmic at MGM on all days with two on the 10th. I would guess Disney thinks the 10th will be crowded, so I would avoid it and choose either the 14th, 15th or 16th.
That leaves AK on 11th, 14th or 15th.
And Epcot on 11th, 14th, or 16th.
So Here is the plan in a nutshell:
10th arrival (MK or Epcot if desired)
11th Epcot or AK
12th MK
13th rest
14th MGM
15th MGM or AK
16th MGM or Epcot
17th Departure (anything but AK)
Happy planning!