tried looking this up but still not positive on the answer:

If you have a themed team but not all the characters on the team have the TA on their dial, are they granted the TA or are they only eligible for the themed team's ATA?

ex: gg Dr. Doom #19 has the Fantastic Four keyword but the Minions of Doom TA on his dial. If I'm running him in a Fantastic Four team, does he automatically get the TA? (crummy example cuz I know he can just wildcard to Fantastic Four, but it illustrates my question).

Nope.

Filler!

Regular Team Abilities have nothing to do with keywords. If you are running a theme team, the figures have their team abilities and that is it.

Now, there are things called Additional Team Abilties. These are based on keywrods, but they do not need to be used on a theme team. Only one ATA can be used per force. If you are using an Additional Team Ability, ALL figures with the qualifying keyword must be assigned the Additional Team Ability, and the cost must be paid for each figure with the keyword.

that brings to mind another question I had:

ALL qualifying characters must be assigned it or as many qualifying characters that you have pts left-over to use it on?

thanks guys for the clarification.

All qualifying characters for an ATA must be assigned it.

Every single character with the prerequisite keyword(s). If that would make you go over on points, then it cannot be used.