I know that long leaders to hootchies are favored up North. I run my leaders (40# or 50# mono or fluoro) 18" to 20" for the hootchies. A lot more action and the fish has to decide it it wants to hit or not. My hook-up ratio went up when I went to the shorter leader. I like a single siwash (5/0 or 6/0) rigged with the end of the tentacles just above the bend of the hook. The short leader also catches Chinook.
For spoons, I'll run about 40-44".
Trolling speed for me is 2.5 to 3.5 mph.