STO Dilemma

I finally made it to rank 4 of the "diplomatic" DOFF ("Duty Officer") missions, which means I can now get one (and only one?) Orion* (female) BOFF ("Bridge Officer").  But which?

Since there are (3) 'classes', there are (3) choices:  Engineering, Science, and Tactical.  I've already got (2) engineering BOFFs, so I ruled that one out.  (I'm leaning towards "science".)

Decisions, decisions...


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* You actually get your choice of either gender (male or female - sorry, no "other", as far as I know) of Orion, Nausicaan, or Gorn.  But why would I want anything other than an Orion female???