Dwayne, First, I'd suggest Uniflow. That would make the engine run richer late in the tank. I would also expect that you might need more pitch...but also less prop load. Increase the pitch toward the last 2" of the tips about 1/4" pitch and see what happens. Worked for me on my .46VF, anyway. It let me richen the engine and lower the launch rpm about 100-200 r's, stopped the lean overhead nonsense, and much better "drive" in the overhead stuff.
It could also be that your pipe is a .32 pipe. I've read of folks running a bit bigger pipe, but I don't think a smaller than normal pipe will ever work well. A lot of it is also the venturi size vs. the muffler/pipe outlet size...read what Randy says about that in his pinned articles. I wish there was a way to ID the pipes somehow. Maybe Randy can make up a chart after the NATS?
Your pipe length (at 18.25") is 5/8" shorter than on my Randy Aero .46VF, and I launch it at around 10.3/10.4k. I've been told that too short is really bad for the engine, creating mucho heat, but I can't say I understand why.
I tried pipe pressure on my .46VF dog. The pipe was fitted with a tap by the previous owner, so I gave it a try, to fix the upwind/downwind, rich/lean nonsense, which it did. But I had trouble with fuel siphoning out of the tank and into the pipe, resulting in unrepeatable run times. Might be easier to deal with on a profile? Fixed that by routing a fuel hose from the external uniflow vent intake into the backplate cavity for a "null" or no pressure area. Works nicely!
Other than that, how's yer neck bones? Mine's about the same...misery. Knee and skin cancer surgeries have kept me down enough, but I've been out bass fishing some!
Steve