I tell anyone who will listen that if they want a more comfortable ride, they should be running the widest tires their frame will allow. A custom frame or a gravel frame is going to expand your horizons on tire width, if you're willing to make the jump. Since mid 2019, I've been rolling almost exclusively on my custom Thompson, 650b 42mm, 40 psi in front, 42 in back. Should I happen to grab my "beater", my custom Rivendell which used to be my pride and joy, I'm on 700c 32mm, 59 psi in front, 70 or so in back. The differences I feel just riding around Austin on those "skinny tires," the bumps on descents I never noticed on my Thompson, really get my attention. Once you go wide, it's hard to go back, even to the standard that you once believed was more than sufficiently comfortable. You can get used to anything-- back in 2005, I was riding centuries (you start randonneuring, you stop using that term) fixed gear on 700c 20mm pumped up to 120 psi. Not much fun when it starts to rain. The confidence the increased contact patch of a wider tire on mountainous descents of 8-9% is an extraordinary advantage as you let it rip, enjoying the payoff of a long grind to the top.
Next stop, raising your bars some. This ain't the Tour de France and your lower back will be happier at the end of a long day in the saddle...
Jeff