What about changing the bar to something like the FSA Metropolis bar. It would bring your hands a little closer in and it has a much better angle for the wrist in my opinion. It also has a small rise to the bar which might help.

The Brooks saddle may indeed need tweaking in the beginning. First when new they are very slippery and that short rails for adjustment aren't ideal. I find that for Brooks, you actually need to point the nose a little higher to counteract the sliding forward.

That is one beautiful bike.