I am no professional by any means but I very rarely ever got skunked and haven't been skunked since I got a fish hawk. My best advice to u is if u have to change plugs every 20 hrs then do it. I have a 1979 75 stinger it is loud! I've never had an issue with it interfering with the fh tho. Try changing the location of the fh that would probably help. I was out this past Sunday and last Sunday and I had to do a surface speed of 5.5-6.2 going west to get my ball speed at 2.6-3.1 heading east surface speed was 1.9-2.2 for down speed to get 2.8-3.4 slowest I could get the boat.
As for leads on my riggers I run about 35-40' back then put the line to my rigger. For my dipsey I run 10foot of lead then hook on my dipsey then another lead to lure 8-10' of fluorocarbon. Lead core I run a 15' fluorocarbon lead.