I would choose to use FP+ if I were you. Although traditionally a lower crowd time, we don't really know what crowds will be like this year, since there is one less week between Thanksgiving and Christmas. Reports recently have indicated that traditional FP have been running out very early for headliner attractions. Furthermore, chances are you will still receive a KTTW card (unless staying at Pop) and may have the ability to pull regular FP as well. I just think your best chance to get headliner attractions done with lower wait times is to book FP+ for the big ones (probably in the afternoon), arrive early and use standby for the first couple hours, and then consider regular FP a bonus if they are available.