My gravel bike has 58mm of trail. I dont find it to be twitchy or sketchy. I dont think about the steering input when climbing or descending, its quite neutral to me, i guess.
admittedly, i dont have 30min climbs or the descents that follow. Mine are a bunch of 5 min climbs over and over.
Perhaps if my descents were minutes on end instead of seconds, I might want a different trail measurement.
The bottom bracket height on your kona is classic CX high, but neednt be for gravel. You can get something at 75m or so and sit in the bike more than on the bike. Its a good feeling.