After 10 hours of comparing every mod against the core, noting every code change by EA, figuring out how it would affect the mods, rebuilding each one against the new core and play testing with the believed compatible mods in for a real hour, I now say with 98% certainty that all mods are compatible with 1.66 except for the following:
ErrorTrap
Traveler
Untranslated Key
and that MasterController is safe to use but it needs a minor update to apply new EA code.
I don't want anyone to let their guard down though. Please, please backup your games if you are going to test these mods on this new patch level. I am not Twallan. I do not know every trick of the core or his mods. I was as thorough as humanly possible for someone who didn't write the code and had several hundred thousands of lines to sort through, but again, I stress I am not him. I will not be changing the patch level compatibly levels on them until several days have passed and no issues are reported.
As for the 3 deemed incompatible and the MC update, I have began updating those and will try to get those out ASAP. Please check back here at a later date.