Personally, I think we should be able to bring our Bridge Officers with us to Defera. It seems kind of daft that every time I go there, the following exchange takes place on my bridge;
"Captain, we have arrived in orbit of Defera. Several Borg ships have landed, and the planet is under sustained attack. Borg drones are spreading across the planet, and the Deferi are struggling to hold them at bay."
"Understood, Number 1. Transporter Room, prepare to beam me down to the surface."
"Err... did you hear what I just said Captain?"
"I certainly did, Number 1. Just me to beam down today."
"Well, I never really liked him anyway."
This character is why I don't play my Romulan any more. Tovan Khev is NOT my BFF! Get him off my bridge!
Its probably to make up for the knowledge is key rooms being so buggy. You can go through the rest of the hard mission easily but that one glitched 80% of the time. They should really fix that. The defera mission are one of my favorite things to do.