Macs are awesome smoked. Hickory is fine for them, I think they use oak up north. Delicious.
I think I would rig a density compensated sinking line one weight over for cod. I tried some deep (very deep) retrieves out in the Straits for coho salmon and have caught deep running salmon. The only thing different was the time you need to wait for the line to sink. You need to play with the current direction too so you keep a slight tension on the line as it sinks.
Some areas bring the fish higher in the column due to the presence of bait and/or upwelling currents. Targeting these areas would also help increase fly catches I assume.