I kind of enjoy racing the kart in the rain. Not that I'm any good at it, I just like it. My first kart rain race, I did a 360 in the first turn on the first lap
. I managed to finish the race though, probably the last kart still running though.
Some tracks are more fun than others. Some tracks feel almost the same in the rain whether you're on slicks or rains, others the traction is very consistent with rain tires. The biggest problem with a kart (or anything I guess) in the rain is they slide about twice as far as the dry when you do crash.
I tried road racing a bike in the rain once, it wasn't too scary considering I was going VERY slow
.