Two suggestions-
First, tip the nose up about 1/8"- your first picture looks like it's tipped down too far and that will make you feel like you are sliding forward off the saddle all the time. I know cause I did that at first. Very uncomfortable sliding feeling! A small change will make a big difference.
Another tip- if your chamois padding is too thick it will get pressed up too much against your girly bits. This can feel bad especially on a Brooks. It starts by feeling numb.

Try to feel your weight on your two sit bones. If you let your back go slack and your stomach sag down while riding lazily, with your weight held up by your hands, your pelvis will then be tilted in such a way as to be riding on your girly parts on the saddle nose, instead of back on your sitbones where your weight should be.

Give it another test ride with the nose tipped up a bit, your back not slack, and less chamois padding.