Thanks Pete, you answered exactly my question, as always !

I'm planning to write a small report about the Honda 150cc, as I will part with it after the October holiday, for a new YBR 250. In the report, I'll mention the tires.
I'm also very cautious in the wet, and this is what is "confidence-destroying": even by being so cautious, with almost no lean at all (maybe 10-15 degrees max), at a very slow speed (15-20 km'h max), and without any acceleration or braking involved, I did 2 slides on the white paint of pedestrian crossings (wide painted lines), the 2nd one sending the kind of terror wave through my spine (you know the kind...) because the rear tire slid for almost all the width of 1 pedestrian crossing line.... I usually avoid those white paint lines as the plague, but it's not always possible.

Of course now I have 0 confidence in those tires in the rain...