I find your analysis good and in my opinion, you come to the right conclusions for you. Maybe because I did something similar :). Here is my personal n=1 experience of the past year:
I went from my endurance road bike with 25mm Conti GP 4000 (with latex inner tubes) to my gravel bike with 2 wheelsets (GP 5000 TL 28mm & WTB Venture 47mm). I love it. This is my one bike to ride everything outside and the old bike is now permanently on the indoor trainer.
Regarding the descending, I never really had any issues with my old bike (endurance, not race geometry), BUT my new setup gives me soooo much more confidence. Not surprisingly, given disc vs rim brakes and the different tires.
Since I’m about the same weight like you, I rode my 25mm (latex tubes) with 70psi front, 75 psi back. The 28mm TL I ride with 55psi/60psi. The wider tires and the drop in pressure make them feel just so much more connected to the street when cornering / descending - no ‘bouncing on the tarmac’, it feels like you are on rails. So with your concerns, I would recommend you going even wider for the 32mm GP 5000 TL. No real harm in doing that (besides minimal aero penalty).