The rectifier/regulator is running a bit on the hot side at 15.3V at only 3000 RPM.
That's pretty close to the red line for a charging system.
I'm wondering if the regulator is starting to go.
For Honda, 15V is the upper limit. Anything more and you run the risk of cooking the battery.
I'd keep track of the charging system output to see if it starts getting higher.
I had a friend's R/R let on his Suzuki 600 go while on a trip and literally blew up the battery and fried every electrical and electronic component on the bike.
Nothing was spared. Anything that sucked electrons got toasted.