I like the idea of trimming the shaft slightly, maybe a half inch. Especially if it's playing over 43" standard. Should cut 3 SW points per half inch, you could add 6g to the head to return the SW to normal at the shorter length. Solves both the SW issue and makes it easier to swing, as well as making it a bit easier to hit solid; just don't get wild with it, use the light weight to make a balanced swing. You'll want to trim from the butt end unless you wish to stiffen the club considerably; It's easier from the butt and many models don't recommend tipping anyway.
However, the 3 wood is a tough club to fit. Heft and length alone might not fix things if it's a ball position or swing issue. I find I can go pretty heavy as long as I don't try to reroute a bad swing at full speed. I stick with swingweights around the low D range for comfort and because it can cause wear and tear on my hands to go hard with heavy clubs.
Personally I have similar profiles and same flex in my 3w and driver, 10g lighter in the driver. I also sometimes carry a 15˚ titanium hybrid that is a cannon at 42" but it's a trifle difficult to hit due to the loft and the sweet spot is a lot smaller both heel to toe and blade to crown vs the 3w.