I'm guessing you haven't been commuting by bike all that long?

Like many things, it's a skill... and you get better at it. You learn what works. You learn what not to try. You figure out what equipment works best.

Goggles are good against bugs, dry snow, and bitter cold. Not much use in rain.

A helmet visor can be good in the rain, but hurt my neck by making me hold my head up straighter than I wanted.

Bonkers drivers? I shifted my schedule so now on my morning commute I hardly see any drivers. There are drivers in the afternoon, but they're all on an early schedule as well, not too impatient yet.

If your hands are slipping off the handlebar, maybe your handlebar is in the wrong position? When my hands are on the bar, they're where they want to be, and they don't slip off.

If you live in an area where it doesn't rain much, a little water is likely to make your roads very slippery. I don't know what it is, but roads are slick when the rain first starts. After they're thoroughly wet traction improves again. I don't blame my tires; I ride cautiously.