Im at 6.3 for republic fleet (and yes its an older character). The nice thing is that the main can share rep gains with his fleet mates so my main picks up the mission, we do it, and my alts are slowly working their reps up too. When they get high enough.. If i draw two missions i dont like on my main, instead of waiting 4 hours before i can reject the 2nd one I can just draw a mission with one of my alts.

I did the math with my friend one time... if i dont have the orca hauling too then yield will be greater with 3 hulks and 1 hauler than with 2 hulks, an orca, and a hauler. I think we calculated you needed 5 or more hulks before it was worthwhile dropping a hulk for the orca... but i dont remember the exact numbers we came up with.