Quick easy question -- Eng or Sci to duo with Tactical?

My wife now wants to play with me and she wants Tactical. What will compliment that best? Engineer for me, or Science? Assuming we duo nearly all the time for the forseeable future aside from Fleet Actions or Open team joins.

Yes, I know it's probably overkill. No, I don't want to go Tactical also; I already have one and want another character to play with her.