I wear specs. I have Rudy Project Rydon with clip-ins.
Just as a BTW, they steam up on very cold mornings when the breeze is faster than I am.
When it rains, I just have to let the rain run off the outer shields.
If the rain is really heavy, I take my specs off and ride into the blur, which is a better view than through water covered plastic.
I have a Giro hat with a peak, which I have removed because its not the sort of thing a roadie has. I didn't see a use for it ( until now ).
There is not much one can do. Motor cyclists attach a short piece of windscreen wiper blade to the index finger of their glove, and give the visor an occasional wipe.
I tried this once. Only once!