You know, I have similar problems on my bike. Once my sit bones are used to riding, the only place I ever have issues is on the soft tissue. I do move around on the saddle quite a bit. It's never distracted from my riding and most of the time, I don't notice I'm doing it. I don't get numbness though...that would worry me.

The one thing that reallly helped me was core strengthening. Next time you are riding, get into position where your butt bones are where they belong on the saddle. Now without moving anything else, contract your abs (pull them toward your spine). Does that lift the soft tissue away from the saddle? For me, it does...instantly. When I've been remiss about my core strength, my saddle discomfort is worse. Not sure if this is your issue or not, but it may help. If you are already a Pilates instructor with a super strong core, forget I said anything!

I would also keep working on the saddle. Have you tried a cut out?

You definitely don't want to tip the saddle forward if its increasing pressure on the hands (I had that, too). I have a seat post with the ability to adjust the tilt without increments (it doesn't have grooves, it has two tension screws). This allowed me to find the exact best spot for front tilt where it gives me as much front relief as possible before increasing the weight on my hands. That might be a possiblity for you if you feel like the saddle is the best you can find.

Good luck with it!!