Welcome Shag !
In my personal opinion it looks to me like the area that restricts performance the most is the head. I have the same bike myself and have been checking out the design of the motor it looks like the heads is the the area I would start with. I do not have much experence with HD motors but have been wrenching on race engines for many years.
I would go with some one who knows a proven combination of performance parts, you can often improve performance and sacrafice reliabilty and rideabilty high performance engines are very high strung and not very sutable for a touring bike. But opening up them heads a litte or replacing could only help.
In my personal opinion it looks to me like the area that restricts performance the most is the head. I have the same bike myself and have been checking out the design of the motor it looks like the heads is the the area I would start with. I do not have much experence with HD motors but have been wrenching on race engines for many years.
I would go with some one who knows a proven combination of performance parts, you can often improve performance and sacrafice reliabilty and rideabilty high performance engines are very high strung and not very sutable for a touring bike. But opening up them heads a litte or replacing could only help.